{"id":18416,"date":"2026-07-19T05:25:21","date_gmt":"2026-07-18T20:25:21","guid":{"rendered":"https:\/\/genai-ai.co.jp\/ai-kanri\/?p=18416"},"modified":"2026-07-19T05:25:21","modified_gmt":"2026-07-18T20:25:21","slug":"cc-c-rand-random","status":"publish","type":"post","link":"https:\/\/genai-ai.co.jp\/ai-kanri\/blog\/cc-c-rand-random\/","title":{"rendered":"\u30102026\u5e747\u6708\u6700\u65b0\u3011C\u8a00\u8a9e\u306e\u4e71\u6570(rand\/srand)\u5b8c\u5168\u30ac\u30a4\u30c9\uff5c\u7bc4\u56f2\u6307\u5b9a\u30fb\u521d\u671f\u5316\u30fb\u5b9f\u8df5\u30b5\u30f3\u30d7\u30eb\u3068Claude Code\u6d3b\u7528\u8853"},"content":{"rendered":"\n<style>\n.g-flow-row{display:flex;gap:8px;justify-content:center;flex-wrap:wrap;align-items:center;}\n.g-flow-item{background:linear-gradient(135deg,#1a1a1a,#2a1015);color:#fff;border-radius:8px;padding:16px 14px;min-width:130px;flex:1;text-align:center;}\n.g-flow-arrow{color:#dc2626;font-size:20px;font-weight:700;}\n.g-card-row{display:flex;gap:12px;flex-wrap:wrap;margin:0 0 32px;}\n.g-card-row>div{flex:1;min-width:220px;}\n@media(max-width:600px){\n  .g-flow-row{flex-direction:column;}\n  .g-flow-arrow{transform:rotate(90deg);}\n  .g-card-row{flex-direction:column;}\n  .g-card-row>div{min-width:100%;}\n}\n<\/style>\n\n\n\n<div style=\"margin:0 0 32px;\">\n  <img decoding=\"async\" src=\"https:\/\/genai-ai.co.jp\/ai-kanri\/wp-content\/uploads\/2026\/07\/thumb-cc-c-rand-random.jpg\" alt=\"\u30102026\u5e747\u6708\u6700\u65b0\u3011C\u8a00\u8a9e\u306e\u4e71\u6570(rand\/srand)\u5b8c\u5168\u30ac\u30a4\u30c9\uff5c\u7bc4\u56f2\u6307\u5b9a\u30fb\u521d\u671f\u5316\u30fb\u5b9f\u8df5\u30b5\u30f3\u30d7\u30eb\u3068Claude Code\u6d3b\u7528\u8853\" style=\"width:100%;height:auto;border-radius:12px;display:block;\">\n<\/div>\n\n\n\n<div style=\"background:#f8f9fa;border-radius:12px;padding:24px 28px;margin:0 0 32px;border-left:4px solid #dc2626;\">\n  <p style=\"font-size:15px;font-weight:700;color:#1a1a1a;margin:0 0 16px;\">\u3053\u306e\u8a18\u4e8b\u306e\u5185\u5bb9<\/p>\n  <ol style=\"margin:0;padding-left:20px;font-size:14px;line-height:2.2;list-style:none;\">\n    <li><a href=\"#sec-01\" style=\"color:#495057;text-decoration:none;\"><span style=\"color:#dc2626;font-weight:700;margin-right:8px;\">01<\/span>\u4e71\u6570\u3068\u306f\u4f55\u304b\uff1a\u771f\u306e\u4e71\u6570\u3068\u7591\u4f3c\u4e71\u6570\u306e\u9055\u3044<\/a><\/li>\n    <li><a href=\"#sec-02\" style=\"color:#495057;text-decoration:none;\"><span style=\"color:#dc2626;font-weight:700;margin-right:8px;\">02<\/span>rand()\u95a2\u6570\u306e\u57fa\u672c\uff1aRAND_MAX\u3068stdlib.h<\/a><\/li>\n    <li><a href=\"#sec-03\" style=\"color:#495057;text-decoration:none;\"><span style=\"color:#dc2626;font-weight:700;margin-right:8px;\">03<\/span>srand()\u3067\u4e71\u6570\u3092\u521d\u671f\u5316\u3059\u308b\uff1atime()\u3068\u306e\u7d44\u307f\u5408\u308f\u305b<\/a><\/li>\n    <li><a href=\"#sec-04\" style=\"color:#495057;text-decoration:none;\"><span style=\"color:#dc2626;font-weight:700;margin-right:8px;\">04<\/span>\u4e71\u6570\u306e\u7bc4\u56f2\u3092\u6307\u5b9a\u3059\u308b\u8a08\u7b97\u5f0f\u3092\u5b8c\u5168\u30de\u30b9\u30bf\u30fc<\/a><\/li>\n    <li><a href=\"#sec-05\" style=\"color:#495057;text-decoration:none;\"><span style=\"color:#dc2626;font-weight:700;margin-right:8px;\">05<\/span>\u5b9f\u8df5\u30b5\u30f3\u30d7\u30eb\u30b3\u30fc\u30c9\u96c6\uff1a\u30b5\u30a4\u30b3\u30ed\u30fb\u3058\u3083\u3093\u3051\u3093\u30fb\u914d\u5217\u30b7\u30e3\u30c3\u30d5\u30eb<\/a><\/li>\n    <li><a href=\"#sec-06\" style=\"color:#495057;text-decoration:none;\"><span style=\"color:#dc2626;font-weight:700;margin-right:8px;\">06<\/span>\u3088\u304f\u3042\u308b\u30df\u30b9\u3068\u843d\u3068\u3057\u7a74\uff1a\u521d\u5b66\u8005\u304c\u5fc5\u305a\u30cf\u30de\u308b\u30dd\u30a4\u30f3\u30c8<\/a><\/li>\n    <li><a href=\"#sec-07\" style=\"color:#495057;text-decoration:none;\"><span style=\"color:#dc2626;font-weight:700;margin-right:8px;\">07<\/span>\u767a\u5c55\uff1a\u3088\u308a\u826f\u3044\u4e71\u6570\u751f\u6210\u306e\u9078\u629e\u80a2<\/a><\/li>\n    <li><a href=\"#sec-08\" style=\"color:#495057;text-decoration:none;\"><span style=\"color:#dc2626;font-weight:700;margin-right:8px;\">08<\/span>Claude Code\u3067C\u8a00\u8a9e\u30b3\u30fc\u30c9\u3092\u81ea\u52d5\u751f\u6210\u3059\u308b<\/a><\/li>\n    <li><a href=\"#faq\" style=\"color:#495057;text-decoration:none;\"><span style=\"color:#dc2626;font-weight:700;margin-right:8px;\">FAQ<\/span>\u3088\u304f\u3042\u308b\u8cea\u554f<\/a><\/li>\n  <\/ol>\n<\/div>\n\n\n\n<p class=\"wp-block-paragraph\">C\u8a00\u8a9e\u3067\u30b2\u30fc\u30e0\u3084\u30b7\u30df\u30e5\u30ec\u30fc\u30b7\u30e7\u30f3\u3092\u4f5c\u3063\u3066\u3044\u308b\u3068\u3001\u5fc5\u305a\u76f4\u9762\u3059\u308b\u306e\u304c\u300c\u4e71\u6570\u306e\u4f7f\u3044\u65b9\u300d\u3067\u3059\u3002\u300crand()\u3092\u4f7f\u3048\u3070\u3044\u3044\u300d\u3068\u306f\u77e5\u3063\u3066\u3044\u308b\u306e\u306b\u3001\u300c\u306a\u305c\u304b\u6bce\u56de\u540c\u3058\u6570\u5b57\u304c\u51fa\u308b\u300d\u300c1\u301c6\u306e\u7bc4\u56f2\u306b\u53ce\u3081\u308b\u306b\u306f\u3069\u3046\u66f8\u3051\u3070\u3044\u3044\uff1f\u300d\u3068\u8a70\u307e\u3063\u3066\u3057\u307e\u3063\u305f\u7d4c\u9a13\u306f\u3042\u308a\u307e\u305b\u3093\u304b\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">C\u8a00\u8a9e\u306e\u4e71\u6570\u751f\u6210\u306b\u306f<strong>rand()\u3068srand()<\/strong>\u3068\u3044\u30462\u3064\u306e\u95a2\u6570\u304c\u4f7f\u308f\u308c\u307e\u3059\u304c\u3001\u521d\u5b66\u8005\u304c\u3064\u307e\u305a\u304d\u3084\u3059\u3044\u306e\u306f\u300c\u521d\u671f\u5316\u306a\u3057\u3067\u306f\u6bce\u56de\u540c\u3058\u5024\u304c\u8fd4\u308b\u300d\u3068\u3044\u3046\u4ed5\u69d8\u3068\u3001\u300c\u7bc4\u56f2\u3092\u6307\u5b9a\u3059\u308b\u305f\u3081\u306e\u8a08\u7b97\u5f0f\u300d\u306e2\u70b9\u3067\u3059\u3002\u3053\u306e\u8a18\u4e8b\u3067\u306f\u3001rand\/srand\u306e\u4ed5\u7d44\u307f\u3092\u6839\u672c\u304b\u3089\u7406\u89e3\u3057\u305f\u3046\u3048\u3067\u3001<strong>\u30b5\u30a4\u30b3\u30ed\u30fb\u3058\u3083\u3093\u3051\u3093\u30fb\u914d\u5217\u30b7\u30e3\u30c3\u30d5\u30eb\u306a\u3069\u5b9f\u8df5\u30b3\u30fc\u30c97\u3064\u4ee5\u4e0a<\/strong>\u3092\u7d39\u4ecb\u3057\u307e\u3059\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u3055\u3089\u306b\u5f8c\u534a\u3067\u306f\u3001<strong>Claude Code\u3092\u4f7f\u3063\u3066C\u8a00\u8a9e\u30b3\u30fc\u30c9\u3092\u81ea\u52d5\u751f\u6210\u3059\u308b\u65b9\u6cd5<\/strong>\u3082\u89e3\u8aac\u3057\u307e\u3059\u3002\u300cC\u8a00\u8a9e\u306e\u30b3\u30fc\u30c9\u3092AI\u306b\u66f8\u304b\u305b\u308b\u300d\u3068\u3044\u3046\u9078\u629e\u80a2\u3092\u77e5\u3063\u3066\u304a\u304f\u3053\u3068\u3067\u3001\u30d7\u30ed\u30b0\u30e9\u30df\u30f3\u30b0\u5b66\u7fd2\u3082\u696d\u52d9\u958b\u767a\u3082\u5927\u5e45\u306b\u52b9\u7387\u5316\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<div class=\"balloon-wrap\">\n  <div class=\"balloon-icon\">\n    <img decoding=\"async\" src=\"https:\/\/genai-ai.co.jp\/ai-kanri\/wp-content\/uploads\/2026\/04\/ceo-sugasawa.jpg\" alt=\"\u4ee3\u8868\u83c5\u6fa4\">\n    <span class=\"balloon-name\">\u4ee3\u8868\u83c5\u6fa4<\/span>\n  <\/div>\n  <div class=\"balloon-body\">\u300c\u4e71\u6570\u306a\u3093\u3066rand()\u306b\u6c7a\u307e\u3063\u3066\u3044\u308b\u300d\u3068\u3044\u3046\u8a8d\u8b58\u3067\u3044\u308b\u3068\u3001\u696d\u52d9\u3084\u7af6\u6280\u30d7\u30ed\u30b0\u30e9\u30df\u30f3\u30b0\u3067\u75db\u3044\u76ee\u3092\u898b\u308b\u3053\u3068\u304c\u3042\u308a\u307e\u3059\u3002C\u8a00\u8a9e\u306erand()\u306f\u300c\u7591\u4f3c\u4e71\u6570\u300d\u3067\u3042\u308a\u3001\u54c1\u8cea\u306b\u306f\u9650\u754c\u304c\u3042\u308a\u307e\u3059\u3002\u3053\u306e\u8a18\u4e8b\u3067\u306f\u57fa\u672c\u304b\u3089\u767a\u5c55\u307e\u3067\u4e00\u6c17\u306b\u89e3\u8aac\u3059\u308b\u306e\u3067\u3001\u3069\u306e\u30ec\u30d9\u30eb\u306e\u8aad\u8005\u306b\u3082\u4f7f\u3048\u308b\u5185\u5bb9\u306b\u306a\u3063\u3066\u3044\u307e\u3059\u3002<\/div>\n<\/div>\n\n\n\n<div class=\"balloon-wrap is-right\">\n  <div class=\"balloon-icon\">\n    <img decoding=\"async\" src=\"https:\/\/genai-ai.co.jp\/ai-kanri\/wp-content\/uploads\/2026\/04\/yamazaki-avatar.png\" alt=\"AI\u9b3c\u7ba1\u7406\u5c71\u5d0e\">\n    <span class=\"balloon-name\">AI\u9b3c\u7ba1\u7406\u5c71\u5d0e<\/span>\n  <\/div>\n  <div class=\"balloon-body\">rand()\u306e\u4ed5\u7d44\u307f\u3092\u6b63\u3057\u304f\u7406\u89e3\u3059\u308b\u3068\u3001\u300c\u306a\u305c\u6bce\u56de\u540c\u3058\u6570\u304c\u51fa\u308b\u306e\u304b\u300d\u300c\u306a\u305csrand(time(NULL))\u304c\u5fc5\u8981\u306a\u306e\u304b\u300d\u304c\u81ea\u7136\u3068\u308f\u304b\u308b\u3088\u3046\u306b\u306a\u308a\u307e\u3059\u3002\u4eca\u65e5\u306f\u305d\u306e\u6d41\u308c\u306b\u6cbf\u3063\u3066\u3001\u9806\u5e8f\u7acb\u3066\u3066\u89e3\u8aac\u3057\u3066\u3044\u304d\u307e\u3059\u3002<\/div>\n<\/div>\n\n\n\n<div style=\"background:#fafafa;border-radius:8px;padding:16px 20px;margin:16px 0;border-left:4px solid #dc2626;\">\n<div style=\"display:flex;align-items:flex-start;gap:8px;padding:6px 0;font-size:15px;line-height:1.6;\"><span style=\"color:#dc2626;font-size:16px;flex-shrink:0;margin-top:2px;\">&#10004;&#65039;<\/span><span><strong>\u4e71\u6570\u30fb\u7591\u4f3c\u4e71\u6570\u30fb\u30b7\u30fc\u30c9<\/strong>\u306e\u9055\u3044\u3092\u6b63\u78ba\u306b\u7406\u89e3\u3059\u308b<\/span><\/div>\n<div style=\"display:flex;align-items:flex-start;gap:8px;padding:6px 0;font-size:15px;line-height:1.6;\"><span style=\"color:#dc2626;font-size:16px;flex-shrink:0;margin-top:2px;\">&#10004;&#65039;<\/span><span><strong>rand()\u95a2\u6570\u306e\u4f7f\u3044\u65b9<\/strong>\u3068RAND_MAX\u306e\u610f\u5473<\/span><\/div>\n<div style=\"display:flex;align-items:flex-start;gap:8px;padding:6px 0;font-size:15px;line-height:1.6;\"><span style=\"color:#dc2626;font-size:16px;flex-shrink:0;margin-top:2px;\">&#10004;&#65039;<\/span><span><strong>srand(time(NULL))\u3067\u521d\u671f\u5316<\/strong>\u3059\u308b\u5fc5\u8981\u6027\u3068\u4ed5\u7d44\u307f<\/span><\/div>\n<div style=\"display:flex;align-items:flex-start;gap:8px;padding:6px 0;font-size:15px;line-height:1.6;\"><span style=\"color:#dc2626;font-size:16px;flex-shrink:0;margin-top:2px;\">&#10004;&#65039;<\/span><span><strong>n\u301cm \u306e\u7bc4\u56f2\u3067\u4e71\u6570\u3092\u751f\u6210\u3059\u308b\u8a08\u7b97\u5f0f<\/strong>\u3092\u5b8c\u5168\u30de\u30b9\u30bf\u30fc<\/span><\/div>\n<div style=\"display:flex;align-items:flex-start;gap:8px;padding:6px 0;font-size:15px;line-height:1.6;\"><span style=\"color:#dc2626;font-size:16px;flex-shrink:0;margin-top:2px;\">&#10004;&#65039;<\/span><span><strong>\u30b5\u30a4\u30b3\u30ed\u30fb\u3058\u3083\u3093\u3051\u3093\u30fb\u914d\u5217\u30b7\u30e3\u30c3\u30d5\u30eb<\/strong>\u306a\u3069\u306e\u5b9f\u8df5\u30b3\u30fc\u30c9<\/span><\/div>\n<div style=\"display:flex;align-items:flex-start;gap:8px;padding:6px 0;font-size:15px;line-height:1.6;\"><span style=\"color:#dc2626;font-size:16px;flex-shrink:0;margin-top:2px;\">&#10004;&#65039;<\/span><span><strong>\u3088\u304f\u3042\u308b\u30d0\u30b0\u3068\u521d\u5b66\u8005\u306e\u843d\u3068\u3057\u7a74<\/strong>\u306e\u89e3\u8aac<\/span><\/div>\n<div style=\"display:flex;align-items:flex-start;gap:8px;padding:6px 0;font-size:15px;line-height:1.6;\"><span style=\"color:#dc2626;font-size:16px;flex-shrink:0;margin-top:2px;\">&#10004;&#65039;<\/span><span><strong>Claude Code<\/strong>\u3067C\u8a00\u8a9e\u30b3\u30fc\u30c9\u3092\u81ea\u52d5\u751f\u6210\u3059\u308b\u65b9\u6cd5<\/span><\/div>\n\n<\/div>\n\n\n<div style=\"margin:48px 0 8px;display:flex;gap:12px;justify-content:center;flex-wrap:wrap;\"><a href=\"https:\/\/aikanri.genai-ai.co.jp\/seminar2-blog\/?utm_source=blog&#038;utm_medium=h2banner&#038;utm_content=cc-c-rand-random&#038;blog_slug=cc-c-rand-random\" target=\"_blank\" rel=\"noopener\" aria-label=\"Claude Code \u5b8c\u5168\u89e3\u8aac\u30bb\u30df\u30ca\u30fc\uff08\u7121\u6599\u30fb1on1\u30fb60\u5206\uff09\u306e\u4e88\u7d04\u753b\u9762\u3078\" style=\"flex:1 1 280px;max-width:360px;text-decoration:none;\"><img decoding=\"async\" src=\"https:\/\/genai-ai.co.jp\/ai-kanri\/wp-content\/uploads\/2026\/05\/cta_seminar_claude_code_2026.jpg\" alt=\"Claude Code \u5b8c\u5168\u89e3\u8aac\u30bb\u30df\u30ca\u30fc\uff5c\u7d4c\u55b6\u8005\u30fb\u4f1a\u793e\u5f79\u54e1\u5c02\u7528 1on1 60\u5206 \u7121\u6599\" style=\"width:100%;height:auto;border-radius:8px;display:block;\"><\/a><a href=\"https:\/\/aikanri.genai-ai.co.jp\/?utm_source=blog&#038;utm_medium=h2banner&#038;utm_campaign=cc-c-rand-random&#038;utm_content=h2-banner-kanri\" target=\"_blank\" rel=\"noopener\" aria-label=\"AI\u9b3c\u7ba1\u7406 \u516c\u5f0f\u30b5\u30a4\u30c8\u3078\" style=\"flex:1 1 280px;max-width:360px;text-decoration:none;\"><img decoding=\"async\" src=\"https:\/\/genai-ai.co.jp\/ai-kanri\/wp-content\/uploads\/2026\/05\/cta_blog_1to1.jpg\" alt=\"Claude Code\u3092\u7d4c\u55b6\u306b\u6d3b\u304b\u3057\u305f\u3044\u65b9\u3078 \u2014 AI\u9b3c\u7ba1\u7406\" style=\"width:100%;height:auto;border-radius:8px;display:block;\"><\/a><\/div>\n\n\n<div id=\"sec-01\"><\/div>\n<h2 class=\"section-header-img\" style=\"margin:32px 0 24px;border-radius:8px;overflow:hidden;background:linear-gradient(135deg,#1a1a1a 0%,#2a1015 100%);padding:32px 28px;color:#fff;position:relative;border:none;border-left:none;text-align:left;\">\n  <span class=\"section-number\" style=\"display:block;\">01<\/span>\n  <span class=\"section-label\" style=\"display:block;\">BASICS<\/span>\n  <span class=\"section-title\" style=\"display:block;\">\u4e71\u6570\u3068\u306f\u4f55\u304b\uff1a\u771f\u306e\u4e71\u6570\u3068\u7591\u4f3c\u4e71\u6570\u306e\u9055\u3044<\/span>\n  <span class=\"section-desc\">C\u8a00\u8a9e\u306erand()\u3092\u6b63\u3057\u304f\u4f7f\u3046\u305f\u3081\u306b\u307e\u305a\u77e5\u3063\u3066\u304a\u304f\u3079\u304d\u57fa\u790e\u77e5\u8b58<\/span>\n<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u4e71\u6570\u3068\u306f\u3001\u30e9\u30f3\u30c0\u30e0\uff08\u7121\u4f5c\u70ba\uff09\u306b\u751f\u6210\u3055\u308c\u308b\u6570\u306e\u3053\u3068\u3067\u3059\u3002\u30b2\u30fc\u30e0\u306e\u30b5\u30a4\u30b3\u30ed\u30fb\u304f\u3058\u5f15\u304d\u30fb\u30b7\u30df\u30e5\u30ec\u30fc\u30b7\u30e7\u30f3\u30fb\u6697\u53f7\u5316\u306a\u3069\u3001\u30b3\u30f3\u30d4\u30e5\u30fc\u30bf\u30d7\u30ed\u30b0\u30e9\u30e0\u3067\u300c\u30e9\u30f3\u30c0\u30e0\u3055\u300d\u304c\u5fc5\u8981\u306a\u3042\u3089\u3086\u308b\u5834\u9762\u3067\u4f7f\u308f\u308c\u307e\u3059\u3002\u3057\u304b\u3057\u3001\u30b3\u30f3\u30d4\u30e5\u30fc\u30bf\u304c\u751f\u6210\u3059\u308b\u4e71\u6570\u306f\u3001\u53b3\u5bc6\u306b\u8a00\u3046\u3068<strong>\u300c\u771f\u306e\u4e71\u6570\u300d\u3067\u306f\u306a\u304f\u300c\u7591\u4f3c\u4e71\u6570\u300d<\/strong>\u3067\u3059\u3002<\/p>\n\n\n\n<div style=\"background:#f8f9fa;border-left:4px solid #6b7280;border-radius:0 8px 8px 0;padding:16px 20px;margin:20px 0;\">\n  <p style=\"margin:0 0 4px;font-size:13px;font-weight:700;color:#6b7280;letter-spacing:1px;\">&#128218; \u7528\u8a9e\u89e3\u8aac<\/p>\n  <p style=\"margin:0;font-size:15px;line-height:1.7;\"><strong>\u771f\u306e\u4e71\u6570\uff08True Random Number\uff09<\/strong>\uff1a\u5b8c\u5168\u306b\u30e9\u30f3\u30c0\u30e0\u3067\u3001\u4e88\u6e2c\u4e0d\u53ef\u80fd\u306a\u4e71\u6570\u3002\u7269\u7406\u7684\u306a\u30ce\u30a4\u30ba\uff08CPU\u6e29\u5ea6\u306e\u63fa\u3089\u304e\u30fb\u30de\u30a6\u30b9\u306e\u52d5\u304d\u30fb\u5927\u6c17\u30ce\u30a4\u30ba\u306a\u3069\uff09\u3092\u5143\u306b\u751f\u6210\u3055\u308c\u308b\u3002\u6697\u53f7\u9375\u306e\u751f\u6210\u306a\u3069\u3001\u30bb\u30ad\u30e5\u30ea\u30c6\u30a3\u304c\u91cd\u8981\u306a\u5834\u9762\u3067\u4f7f\u308f\u308c\u308b\u3002Linux\u3067\u306fOS \u304c\u30a8\u30f3\u30c8\u30ed\u30d4\u30fc\u3092\u96c6\u3081\u3066 \/dev\/urandom \u7b49\u3067\u63d0\u4f9b\u3059\u308b\u3002<\/p>\n<\/div>\n\n\n\n<div style=\"background:#f8f9fa;border-left:4px solid #6b7280;border-radius:0 8px 8px 0;padding:16px 20px;margin:20px 0;\">\n  <p style=\"margin:0 0 4px;font-size:13px;font-weight:700;color:#6b7280;letter-spacing:1px;\">&#128218; \u7528\u8a9e\u89e3\u8aac<\/p>\n  <p style=\"margin:0;font-size:15px;line-height:1.7;\"><strong>\u7591\u4f3c\u4e71\u6570\uff08Pseudo-Random Number\uff09<\/strong>\uff1a\u30a2\u30eb\u30b4\u30ea\u30ba\u30e0\u306b\u3088\u3063\u3066\u8a08\u7b97\u3067\u751f\u6210\u3055\u308c\u308b\u300c\u30e9\u30f3\u30c0\u30e0\u306b\u898b\u3048\u308b\u6570\u5217\u300d\u3002\u540c\u3058\u30b7\u30fc\u30c9\uff08\u521d\u671f\u5024\uff09\u3092\u4e0e\u3048\u308c\u3070\u3001\u5fc5\u305a\u540c\u3058\u6570\u5217\u304c\u518d\u73fe\u3055\u308c\u308b\u3002C\u8a00\u8a9e\u306erand()\u304c\u751f\u6210\u3059\u308b\u306e\u306f\u3053\u306e\u7591\u4f3c\u4e71\u6570\u3002\u7d71\u8a08\u7684\u306b\u306f\u30e9\u30f3\u30c0\u30e0\u306b\u898b\u3048\u308b\u304c\u3001\u539f\u7406\u7684\u306b\u306f\u4e88\u6e2c\u53ef\u80fd\u3002<\/p>\n<\/div>\n\n\n\n<p class=\"wp-block-paragraph\">C\u8a00\u8a9e\u306e<code>rand()<\/code>\u95a2\u6570\u306f<strong>\u7dda\u5f62\u5408\u540c\u6cd5\uff08LCG: Linear Congruential Generator\uff09<\/strong>\u3068\u3044\u3046\u30a2\u30eb\u30b4\u30ea\u30ba\u30e0\u3067\u52d5\u4f5c\u3057\u3066\u3044\u307e\u3059\u3002\u524d\u306e\u5024\u306b\u7279\u5b9a\u306e\u4fc2\u6570\u3092\u639b\u3051\u3066\u3001\u7279\u5b9a\u306e\u6570\u3067\u5272\u3063\u305f\u4f59\u308a\u3092\u6b21\u306e\u5024\u3068\u3059\u308b\u3001\u3068\u3044\u3046\u30b7\u30f3\u30d7\u30eb\u306a\u8a08\u7b97\u3092\u7e70\u308a\u8fd4\u3057\u3066\u3044\u307e\u3059\u3002<\/p>\n\n\n\n<div style=\"background:#f8f9fa;border-left:4px solid #6b7280;border-radius:0 8px 8px 0;padding:16px 20px;margin:20px 0;\">\n  <p style=\"margin:0 0 4px;font-size:13px;font-weight:700;color:#6b7280;letter-spacing:1px;\">&#128218; \u7528\u8a9e\u89e3\u8aac<\/p>\n  <p style=\"margin:0;font-size:15px;line-height:1.7;\"><strong>\u30b7\u30fc\u30c9\uff08Seed\uff09<\/strong>\uff1a\u7591\u4f3c\u4e71\u6570\u751f\u6210\u306e\u300c\u521d\u671f\u5024\u300d\u3002\u540c\u3058\u30b7\u30fc\u30c9\u304b\u3089\u306f\u5fc5\u305a\u540c\u3058\u4e71\u6570\u5217\u304c\u751f\u6210\u3055\u308c\u308b\u3002srand()\u95a2\u6570\u3067\u30b7\u30fc\u30c9\u3092\u8a2d\u5b9a\u3059\u308b\u3002\u521d\u671f\u5316\u306a\u3057\uff08srand\u672a\u547c\u3073\u51fa\u3057\uff09\u306e\u5834\u5408\u306f\u3001\u30b7\u30fc\u30c9\u304c\u56fa\u5b9a\u5024\uff08\u901a\u5e381\uff09\u306b\u8a2d\u5b9a\u3055\u308c\u308b\u305f\u3081\u3001\u6bce\u56de\u540c\u3058\u4e71\u6570\u5217\u304c\u8fd4\u308b\u3002<\/p>\n<\/div>\n\n\n\n<p class=\"wp-block-paragraph\">\u91cd\u8981\u306a\u30dd\u30a4\u30f3\u30c8\u3092\u78ba\u8a8d\u3057\u3066\u304a\u304d\u307e\u3057\u3087\u3046\u3002C\u8a00\u8a9e\u306erand()\u306f\u3001\u30b7\u30fc\u30c9\u5024\u304c\u6c7a\u307e\u308b\u3068<strong>\u751f\u6210\u3055\u308c\u308b\u6570\u5217\u306f\u5b8c\u5168\u306b\u6c7a\u5b9a\u8ad6\u7684\uff08deterministic\uff09<\/strong>\u3067\u3059\u3002\u3064\u307e\u308a\u3001\u30b7\u30fc\u30c9=1\u306a\u3089\u5e38\u306b\u300c41, 18467, 6334, 26500, ...\u300d\u3068\u3044\u3046\u540c\u3058\u6570\u5217\u304c\u751f\u6210\u3055\u308c\u307e\u3059\u3002\u3053\u308c\u304c\u300c\u521d\u671f\u5316\u3057\u306a\u3044\u3068\u6bce\u56de\u540c\u3058\u6570\u304c\u51fa\u308b\u300d\u73fe\u8c61\u306e\u539f\u56e0\u3067\u3059\u3002<\/p>\n\n\n\n<div class=\"g-flow-row\" style=\"margin:24px 0;\">\n  <div class=\"g-flow-item\"><strong>\u30b7\u30fc\u30c9\uff08\u521d\u671f\u5024\uff09\u3092\u8a2d\u5b9a<\/strong><br><span style=\"font-size:12px;\">srand()\u3067\u8a2d\u5b9a<br>\u672a\u8a2d\u5b9a\u306a\u3089\u30b7\u30fc\u30c9=1<\/span><\/div>\n  <div class=\"g-flow-arrow\">&#8594;<\/div>\n  <div class=\"g-flow-item\"><strong>\u7dda\u5f62\u5408\u540c\u6cd5\u3067\u8a08\u7b97<\/strong><br><span style=\"font-size:12px;\">\u524d\u306e\u5024\u00d7\u4fc2\u6570+\u52a0\u6570<br>\u3092\u6c7a\u307e\u3063\u305f\u6570\u3067\u5272\u308b<\/span><\/div>\n  <div class=\"g-flow-arrow\">&#8594;<\/div>\n  <div class=\"g-flow-item\"><strong>\u4f59\u308a\u3092\u4e71\u6570\u3068\u3057\u3066\u8fd4\u3059<\/strong><br><span style=\"font-size:12px;\">0\u301cRAND_MAX<br>\u306e\u6574\u6570\u5024<\/span><\/div>\n  <div class=\"g-flow-arrow\">&#8594;<\/div>\n  <div class=\"g-flow-item\"><strong>\u6b21\u306e\u547c\u3073\u51fa\u3057\u306b\u5099\u3048\u308b<\/strong><br><span style=\"font-size:12px;\">\u4eca\u306e\u5024\u3092\u6b21\u306e\u8a08\u7b97\u306e<br>\u300c\u524d\u306e\u5024\u300d\u3068\u3057\u3066\u4fdd\u6301<\/span><\/div>\n<\/div>\n\n\n\n<div class=\"balloon-wrap is-right\">\n  <div class=\"balloon-icon\">\n    <img decoding=\"async\" src=\"https:\/\/genai-ai.co.jp\/ai-kanri\/wp-content\/uploads\/2026\/04\/yamazaki-avatar.png\" alt=\"AI\u9b3c\u7ba1\u7406\u5c71\u5d0e\">\n    <span class=\"balloon-name\">AI\u9b3c\u7ba1\u7406\u5c71\u5d0e<\/span>\n  <\/div>\n  <div class=\"balloon-body\">\u300c\u6bce\u56de\u540c\u3058\u6570\u304c\u51fa\u308b\u300d\u306e\u306f\u30d0\u30b0\u3067\u306f\u306a\u304f\u3001\u7591\u4f3c\u4e71\u6570\u306e\u8a2d\u8a08\u4e0a\u306e\u7279\u6027\u3067\u3059\u3002\u30b7\u30fc\u30c9\u304c\u56fa\u5b9a\u306a\u3089\u6570\u5217\u306f\u56fa\u5b9a\u3002\u3060\u304b\u3089\u300c\u6bce\u56de\u9055\u3046\u6570\u3092\u51fa\u3059\u306b\u306f\u3001\u6bce\u56de\u9055\u3046\u30b7\u30fc\u30c9\u3092\u8a2d\u5b9a\u3057\u306a\u3051\u308c\u3070\u306a\u3089\u306a\u3044\u300d\u3068\u3044\u3046\u308f\u3051\u3067\u3059\u3002\u3053\u3053\u3092\u7406\u89e3\u3059\u308c\u3070\u3001srand(time(NULL))\u306e\u610f\u5473\u304c\u81ea\u7136\u3068\u308f\u304b\u308a\u307e\u3059\u3002<\/div>\n<\/div>\n\n\n<div style=\"margin:48px 0 8px;display:flex;gap:12px;justify-content:center;flex-wrap:wrap;\"><a href=\"https:\/\/aikanri.genai-ai.co.jp\/seminar2-blog\/?utm_source=blog&#038;utm_medium=h2banner&#038;utm_content=cc-c-rand-random&#038;blog_slug=cc-c-rand-random\" target=\"_blank\" rel=\"noopener\" aria-label=\"Claude Code \u5b8c\u5168\u89e3\u8aac\u30bb\u30df\u30ca\u30fc\uff08\u7121\u6599\u30fb1on1\u30fb60\u5206\uff09\u306e\u4e88\u7d04\u753b\u9762\u3078\" style=\"flex:1 1 280px;max-width:360px;text-decoration:none;\"><img decoding=\"async\" src=\"https:\/\/genai-ai.co.jp\/ai-kanri\/wp-content\/uploads\/2026\/05\/cta_seminar_claude_code_2026.jpg\" alt=\"Claude Code \u5b8c\u5168\u89e3\u8aac\u30bb\u30df\u30ca\u30fc\uff5c\u7d4c\u55b6\u8005\u30fb\u4f1a\u793e\u5f79\u54e1\u5c02\u7528 1on1 60\u5206 \u7121\u6599\" style=\"width:100%;height:auto;border-radius:8px;display:block;\"><\/a><a href=\"https:\/\/aikanri.genai-ai.co.jp\/?utm_source=blog&#038;utm_medium=h2banner&#038;utm_campaign=cc-c-rand-random&#038;utm_content=h2-banner-kanri\" target=\"_blank\" rel=\"noopener\" aria-label=\"AI\u9b3c\u7ba1\u7406 \u516c\u5f0f\u30b5\u30a4\u30c8\u3078\" style=\"flex:1 1 280px;max-width:360px;text-decoration:none;\"><img decoding=\"async\" src=\"https:\/\/genai-ai.co.jp\/ai-kanri\/wp-content\/uploads\/2026\/05\/cta_blog_1to1.jpg\" alt=\"Claude Code\u3092\u7d4c\u55b6\u306b\u6d3b\u304b\u3057\u305f\u3044\u65b9\u3078 \u2014 AI\u9b3c\u7ba1\u7406\" style=\"width:100%;height:auto;border-radius:8px;display:block;\"><\/a><\/div>\n\n\n<div id=\"sec-02\"><\/div>\n<h2 class=\"section-header-img\" style=\"margin:32px 0 24px;border-radius:8px;overflow:hidden;background:linear-gradient(135deg,#1a1a1a 0%,#2a1015 100%);padding:32px 28px;color:#fff;position:relative;border:none;border-left:none;text-align:left;\">\n  <span class=\"section-number\" style=\"display:block;\">02<\/span>\n  <span class=\"section-label\" style=\"display:block;\">RAND FUNCTION<\/span>\n  <span class=\"section-title\" style=\"display:block;\">rand()\u95a2\u6570\u306e\u57fa\u672c\uff1aRAND_MAX\u3068stdlib.h<\/span>\n  <span class=\"section-desc\">\u4e71\u6570\u751f\u6210\u306e\u4e2d\u5fc3\u3068\u306a\u308brand()\u306e\u4ed5\u69d8\u3092\u6b63\u78ba\u306b\u628a\u63e1\u3059\u308b<\/span>\n<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">C\u8a00\u8a9e\u306erand()\u95a2\u6570\u306f\u3001<code>&lt;stdlib.h&gt;<\/code>\u30d8\u30c3\u30c0\u3092\u30a4\u30f3\u30af\u30eb\u30fc\u30c9\u3059\u308b\u3053\u3068\u3067\u4f7f\u3048\u307e\u3059\u3002\u3053\u306e\u95a2\u6570\u306f\u547c\u3073\u51fa\u3059\u305f\u3073\u306b0\u304b\u3089<strong>RAND_MAX<\/strong>\u307e\u3067\u306e\u6574\u6570\u3092\u3072\u3068\u3064\u8fd4\u3057\u307e\u3059\u3002<\/p>\n\n\n\n<div style=\"background:#f8f9fa;border-left:4px solid #6b7280;border-radius:0 8px 8px 0;padding:16px 20px;margin:20px 0;\">\n  <p style=\"margin:0 0 4px;font-size:13px;font-weight:700;color:#6b7280;letter-spacing:1px;\">&#128218; \u7528\u8a9e\u89e3\u8aac<\/p>\n  <p style=\"margin:0;font-size:15px;line-height:1.7;\"><strong>RAND_MAX<\/strong>\uff1arand()\u95a2\u6570\u304c\u8fd4\u3059\u4e71\u6570\u306e\u6700\u5927\u5024\u3002stdlib.h\u3067\u5b9a\u7fa9\u3055\u308c\u308b\u30de\u30af\u30ed\u5b9a\u6570\u3002C\u8a00\u8a9e\u306e\u898f\u683c\u3067\u306fRAND_MAX\u306f\u5c11\u306a\u304f\u3068\u308232767\u4ee5\u4e0a\u3067\u3042\u308b\u3053\u3068\u304c\u4fdd\u8a3c\u3055\u308c\u3066\u3044\u308b\u304c\u3001\u591a\u304f\u306e\u74b0\u5883\u3067\u306f2,147,483,647\uff082^31-1\uff09\u307e\u305f\u306f32767\uff082^15-1\uff09\u306b\u306a\u308b\u3002Linux\u3067\u306fgcc\u4f7f\u7528\u6642\u306f2,147,483,647\u304c\u4e00\u822c\u7684\u3002<\/p>\n<\/div>\n\n\n\n<h3 class=\"wp-block-heading\">2-1. rand()\u306e\u6700\u3082\u57fa\u672c\u7684\u306a\u4f7f\u3044\u65b9<\/h3>\n\n\n\n<div style=\"background:#1e1e1e;border-radius:8px;padding:20px 24px;margin:20px 0;overflow-x:auto;\">\n  <pre style=\"margin:0;color:#d4d4d4;font-size:13px;line-height:1.8;font-family:'Consolas','Courier New',monospace;white-space:pre;\">#include <stdio.h>\n#include <stdlib.h>   \/* rand(), RAND_MAX\u3092\u4f7f\u3046\u305f\u3081\u306b\u5fc5\u8981 *\/\n\nint main(void) {\n    int i;\n\n    \/* rand()\u30675\u500b\u306e\u4e71\u6570\u3092\u751f\u6210\u3057\u3066\u8868\u793a *\/\n    for (i = 0; i < 5; i++) {\n        printf(\"\u4e71\u6570[%d]: %d\\n\", i, rand());\n    }\n\n    \/* RAND_MAX\u306e\u5024\u3092\u78ba\u8a8d *\/\n    printf(\"RAND_MAX\u306e\u5024: %d\\n\", RAND_MAX);\n\n    return 0;\n}<\/pre>\n<\/div>\n\n\n\n<p class=\"wp-block-paragraph\">\u4e0a\u8a18\u306e\u30b3\u30fc\u30c9\u3092\u5b9f\u884c\u3059\u308b\u3068\u30010\u301cRAND_MAX\u306e\u7bc4\u56f2\u306e\u6574\u6570\u304c5\u3064\u51fa\u529b\u3055\u308c\u307e\u3059\u3002\u91cd\u8981\u306a\u306e\u306f\u3001<strong>srand()\u3067\u521d\u671f\u5316\u3057\u3066\u3044\u306a\u3044\u5834\u5408\u3001\u4f55\u56de\u5b9f\u884c\u3057\u3066\u3082\u540c\u3058\u6570\u304c\u51fa\u529b\u3055\u308c\u308b<\/strong>\u3068\u3044\u3046\u70b9\u3067\u3059\u3002<\/p>\n\n\n\n<div style=\"background:#f0fdf4;border:1px solid #22c55e;border-radius:8px;padding:20px 24px;margin:24px 0;\">\n  <div style=\"display:flex;align-items:center;gap:8px;margin-bottom:12px;\">\n    <span style=\"font-size:18px;\">&#128161;<\/span>\n    <strong style=\"color:#16a34a;font-size:15px;\">stdlib.h\u306e\u30a4\u30f3\u30af\u30eb\u30fc\u30c9\u3092\u5fd8\u308c\u305a\u306b<\/strong>\n  <\/div>\n  <p style=\"margin:0;font-size:15px;line-height:1.8;color:#333;\">rand()\u3068srand()\u306f\u3069\u3061\u3089\u3082<stdlib.h>\u306b\u5b9a\u7fa9\u3055\u308c\u3066\u3044\u308b\u305f\u3081\u3001\u3053\u306e\u30d8\u30c3\u30c0\u306e\u30a4\u30f3\u30af\u30eb\u30fc\u30c9\u304c\u5fc5\u9808\u3067\u3059\u3002\u30a4\u30f3\u30af\u30eb\u30fc\u30c9\u3092\u5fd8\u308c\u308b\u3068\u300c\u6697\u9ed9\u306e\u95a2\u6570\u5ba3\u8a00\u300d\u3068\u3057\u3066\u6271\u308f\u308c\u3001\u30b3\u30f3\u30d1\u30a4\u30eb\u306f\u901a\u3063\u3066\u3082\u5b9f\u884c\u6642\u306b\u4e88\u671f\u3057\u306a\u3044\u5024\u304c\u8fd4\u308b\u3053\u3068\u304c\u3042\u308a\u307e\u3059\uff08\u7279\u306b64bit\u74b0\u5883\u3067\u554f\u984c\u306b\u306a\u308a\u3084\u3059\u3044\uff09\u3002<\/p>\n<\/div>\n\n\n\n<h3 class=\"wp-block-heading\">2-2. RAND_MAX\u306e\u74b0\u5883\u4f9d\u5b58\u6027\u3092\u7406\u89e3\u3059\u308b<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">RAND_MAX\u306e\u5024\u306f\u74b0\u5883\uff08OS\u30fb\u30b3\u30f3\u30d1\u30a4\u30e9\uff09\u306b\u3088\u3063\u3066\u7570\u306a\u308a\u307e\u3059\u3002\u7279\u306b\u6ce8\u610f\u304c\u5fc5\u8981\u306a\u306e\u306f\u3001Windows\uff08MSVC\uff09\u306e\u5834\u5408RAND_MAX\u304c32767\u306b\u8a2d\u5b9a\u3055\u308c\u3066\u3044\u308b\u30b1\u30fc\u30b9\u304c\u591a\u3044\u70b9\u3067\u3059\u3002\u3053\u308c\u306f<strong>2^15-1 = 32767<\/strong>\u3067\u3001C\u8a00\u8a9e\u898f\u683c\u304c\u8981\u6c42\u3059\u308b\u6700\u5c0f\u5024\u3067\u3059\u3002<\/p>\n\n\n\n<table>\n<thead><tr><th>\u74b0\u5883<\/th><th>RAND_MAX\u306e\u5178\u578b\u5024<\/th><th>\u5099\u8003<\/th><\/tr><\/thead>\n<tbody>\n<tr><td>Linux (gcc)<\/td><td>2,147,483,647 (2^31-1)<\/td><td>\u9ad8\u54c1\u8cea\u306a\u4e71\u6570\u7bc4\u56f2<\/td><\/tr>\n<tr><td>macOS (clang)<\/td><td>2,147,483,647 (2^31-1)<\/td><td>\u540c\u4e0a<\/td><\/tr>\n<tr><td>Windows (MSVC)<\/td><td>32,767 (2^15-1)<\/td><td>\u7bc4\u56f2\u304c\u72ed\u304f\u6ce8\u610f\u304c\u5fc5\u8981<\/td><\/tr>\n<tr><td>\u7d44\u307f\u8fbc\u307f\u7cfb<\/td><td>\u5b9f\u88c5\u4f9d\u5b58<\/td><td>\u30de\u30cb\u30e5\u30a2\u30eb\u78ba\u8a8d\u5fc5\u9808<\/td><\/tr>\n<\/tbody>\n<\/table>\n\n\n\n<div style=\"background:#fef2f2;border:2px solid #dc2626;border-radius:8px;padding:20px 24px;margin:24px 0;\">\n  <div style=\"display:flex;align-items:center;gap:8px;margin-bottom:12px;\">\n    <span style=\"font-size:20px;\">&#9888;&#65039;<\/span>\n    <strong style=\"color:#dc2626;font-size:16px;\">Windows\u74b0\u5883\u3067rand()\u3092\u4f7f\u3046\u969b\u306e\u6ce8\u610f<\/strong>\n  <\/div>\n  <p style=\"margin:0;font-size:15px;line-height:1.8;color:#333;\">Windows\u306eMSVC\u30b3\u30f3\u30d1\u30a4\u30e9\u3067\u306f RAND_MAX = 32767 \u3067\u3059\u3002\u3053\u308c\u306f\u6700\u5927\u3067\u308232767\u7a2e\u985e\u306e\u5024\u3057\u304b\u751f\u6210\u3067\u304d\u306a\u3044\u3053\u3068\u3092\u610f\u5473\u3057\u307e\u3059\u3002\u305f\u3068\u3048\u3070\u300c100\u4e07\u901a\u308a\u306e\u30e9\u30f3\u30c0\u30e0\u30c7\u30fc\u30bf\u304c\u5fc5\u8981\u300d\u306a\u30b1\u30fc\u30b9\u3067\u306f RAND_MAX \u304c\u8db3\u308a\u306a\u304f\u306a\u308a\u307e\u3059\u3002\u3053\u306e\u5834\u5408\u306f\u300crand() * (RAND_MAX + 1) + rand()\u300d\u306e\u3088\u3046\u306b\u7d44\u307f\u5408\u308f\u305b\u308b\u304b\u3001\u5f8c\u8ff0\u306e\u3088\u308a\u54c1\u8cea\u306e\u9ad8\u3044\u4e71\u6570\u751f\u6210\u65b9\u6cd5\u3092\u4f7f\u3046\u5fc5\u8981\u304c\u3042\u308a\u307e\u3059\u3002<\/p>\n<\/div>\n\n\n\n<div class=\"balloon-wrap\">\n  <div class=\"balloon-icon\">\n    <img decoding=\"async\" src=\"https:\/\/genai-ai.co.jp\/ai-kanri\/wp-content\/uploads\/2026\/04\/ceo-sugasawa.jpg\" alt=\"\u4ee3\u8868\u83c5\u6fa4\">\n    <span class=\"balloon-name\">\u4ee3\u8868\u83c5\u6fa4<\/span>\n  <\/div>\n  <div class=\"balloon-body\">RAND_MAX\u304c32767\u30682,147,483,647\u3067\u306f\u5929\u3068\u5730\u306e\u5dee\u304c\u3042\u308a\u307e\u3059\u3002Windows\u3067\u958b\u767a\u3057\u305f\u4e71\u6570\u30b3\u30fc\u30c9\u3092Linux\u306b\u79fb\u690d\u3059\u308b\u3068\u6319\u52d5\u304c\u5909\u308f\u308b\u3053\u3068\u304c\u3042\u308b\u306e\u306f\u3001\u3053\u306e\u5dee\u304c\u539f\u56e0\u3067\u3059\u3002\u30dd\u30fc\u30bf\u30d3\u30ea\u30c6\u30a3\u3092\u610f\u8b58\u3057\u305f\u30b3\u30fc\u30c9\u3067\u306f\u3001RAND_MAX\u306e\u5024\u3092\u524d\u63d0\u3068\u3057\u306a\u3044\u5b9f\u88c5\u3092\u5fc3\u304c\u3051\u308b\u3053\u3068\u304c\u5927\u5207\u3067\u3059\u3002<\/div>\n<\/div>\n\n\n<div style=\"margin:48px 0 8px;display:flex;gap:12px;justify-content:center;flex-wrap:wrap;\"><a href=\"https:\/\/aikanri.genai-ai.co.jp\/seminar2-blog\/?utm_source=blog&#038;utm_medium=h2banner&#038;utm_content=cc-c-rand-random&#038;blog_slug=cc-c-rand-random\" target=\"_blank\" rel=\"noopener\" aria-label=\"Claude Code \u5b8c\u5168\u89e3\u8aac\u30bb\u30df\u30ca\u30fc\uff08\u7121\u6599\u30fb1on1\u30fb60\u5206\uff09\u306e\u4e88\u7d04\u753b\u9762\u3078\" style=\"flex:1 1 280px;max-width:360px;text-decoration:none;\"><img decoding=\"async\" src=\"https:\/\/genai-ai.co.jp\/ai-kanri\/wp-content\/uploads\/2026\/05\/cta_seminar_claude_code_2026.jpg\" alt=\"Claude Code \u5b8c\u5168\u89e3\u8aac\u30bb\u30df\u30ca\u30fc\uff5c\u7d4c\u55b6\u8005\u30fb\u4f1a\u793e\u5f79\u54e1\u5c02\u7528 1on1 60\u5206 \u7121\u6599\" style=\"width:100%;height:auto;border-radius:8px;display:block;\"><\/a><a href=\"https:\/\/aikanri.genai-ai.co.jp\/?utm_source=blog&#038;utm_medium=h2banner&#038;utm_campaign=cc-c-rand-random&#038;utm_content=h2-banner-kanri\" target=\"_blank\" rel=\"noopener\" aria-label=\"AI\u9b3c\u7ba1\u7406 \u516c\u5f0f\u30b5\u30a4\u30c8\u3078\" style=\"flex:1 1 280px;max-width:360px;text-decoration:none;\"><img decoding=\"async\" src=\"https:\/\/genai-ai.co.jp\/ai-kanri\/wp-content\/uploads\/2026\/05\/cta_blog_1to1.jpg\" alt=\"Claude Code\u3092\u7d4c\u55b6\u306b\u6d3b\u304b\u3057\u305f\u3044\u65b9\u3078 \u2014 AI\u9b3c\u7ba1\u7406\" style=\"width:100%;height:auto;border-radius:8px;display:block;\"><\/a><\/div>\n\n\n<div id=\"sec-03\"><\/div>\n<h2 class=\"section-header-img\" style=\"margin:32px 0 24px;border-radius:8px;overflow:hidden;background:linear-gradient(135deg,#1a1a1a 0%,#2a1015 100%);padding:32px 28px;color:#fff;position:relative;border:none;border-left:none;text-align:left;\">\n  <span class=\"section-number\" style=\"display:block;\">03<\/span>\n  <span class=\"section-label\" style=\"display:block;\">SRAND INIT<\/span>\n  <span class=\"section-title\" style=\"display:block;\">srand()\u3067\u4e71\u6570\u3092\u521d\u671f\u5316\u3059\u308b\uff1atime()\u3068\u306e\u7d44\u307f\u5408\u308f\u305b<\/span>\n  <span class=\"section-desc\">\u6bce\u56de\u7570\u306a\u308b\u4e71\u6570\u5217\u3092\u5f97\u308b\u305f\u3081\u306e\u6a19\u6e96\u7684\u306a\u521d\u671f\u5316\u30d1\u30bf\u30fc\u30f3<\/span>\n<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">rand()\u3067\u6bce\u56de\u7570\u306a\u308b\u4e71\u6570\u5217\u3092\u5f97\u308b\u306b\u306f\u3001<strong>srand()\u95a2\u6570\u3067\u30b7\u30fc\u30c9\u3092\u8a2d\u5b9a<\/strong>\u3059\u308b\u5fc5\u8981\u304c\u3042\u308a\u307e\u3059\u3002srand()\u306e\u5f15\u6570\u3068\u3057\u3066\u300c\u6bce\u56de\u7570\u306a\u308b\u5024\u300d\u3092\u6e21\u3059\u3053\u3068\u3067\u3001\u4e71\u6570\u5217\u304c\u5909\u308f\u308a\u307e\u3059\u3002<\/p>\n\n\n\n<div style=\"background:#f8f9fa;border-left:4px solid #6b7280;border-radius:0 8px 8px 0;padding:16px 20px;margin:20px 0;\">\n  <p style=\"margin:0 0 4px;font-size:13px;font-weight:700;color:#6b7280;letter-spacing:1px;\">&#128218; \u7528\u8a9e\u89e3\u8aac<\/p>\n  <p style=\"margin:0;font-size:15px;line-height:1.7;\"><strong>srand()\uff08\u30b7\u30fc\u30c9\u8a2d\u5b9a\u95a2\u6570\uff09<\/strong>\uff1arand()\u304c\u4f7f\u3046\u4e71\u6570\u5217\u306e\u51fa\u767a\u70b9\uff08\u30b7\u30fc\u30c9\uff09\u3092\u8a2d\u5b9a\u3059\u308b\u95a2\u6570\u3002\u540c\u3058\u30b7\u30fc\u30c9\u3092\u6e21\u3059\u3068\u540c\u3058\u4e71\u6570\u5217\u304c\u751f\u6210\u3055\u308c\u308b\u3002\u4e00\u822c\u7684\u306b\u306fsrand(time(NULL))\u3068\u66f8\u304d\u3001\u73fe\u5728\u306eUnix\u30bf\u30a4\u30e0\uff081970\u5e741\u67081\u65e5\u304b\u3089\u306e\u7d4c\u904e\u79d2\u6570\uff09\u3092\u30b7\u30fc\u30c9\u3068\u3057\u3066\u4f7f\u3046\u3002\u30d7\u30ed\u30b0\u30e9\u30e0\u8d77\u52d5\u3054\u3068\u306b\u6642\u523b\u304c\u5909\u308f\u308b\u305f\u3081\u3001\u6bce\u56de\u9055\u3046\u4e71\u6570\u5217\u306b\u306a\u308b\u3002<\/p>\n<\/div>\n\n\n\n<h3 class=\"wp-block-heading\">3-1. srand(time(NULL))\u306e\u6a19\u6e96\u7684\u306a\u66f8\u304d\u65b9<\/h3>\n\n\n\n<div style=\"background:#1e1e1e;border-radius:8px;padding:20px 24px;margin:20px 0;overflow-x:auto;\">\n  <pre style=\"margin:0;color:#d4d4d4;font-size:13px;line-height:1.8;font-family:'Consolas','Courier New',monospace;white-space:pre;\">#include <stdio.h>\n#include <stdlib.h>   \/* rand(), srand() *\/\n#include <time.h>     \/* time() *\/\n\nint main(void) {\n    int i;\n\n    \/* \u73fe\u5728\u6642\u523b\u3092\u30b7\u30fc\u30c9\u306b\u3057\u3066\u4e71\u6570\u5217\u3092\u521d\u671f\u5316 *\/\n    srand((unsigned int)time(NULL));\n\n    \/* rand()\u30675\u500b\u306e\u4e71\u6570\u3092\u751f\u6210\u3057\u3066\u8868\u793a *\/\n    for (i = 0; i < 5; i++) {\n        printf(\"\u4e71\u6570[%d]: %d\\n\", i, rand());\n    }\n\n    return 0;\n}<\/pre>\n<\/div>\n\n\n\n<p class=\"wp-block-paragraph\">\u3053\u306e\u30b3\u30fc\u30c9\u3092\u5b9f\u884c\u3059\u308b\u305f\u3073\u306b\u3001\u7570\u306a\u308b\u6570\u5217\u304c\u51fa\u529b\u3055\u308c\u307e\u3059\u3002\u30dd\u30a4\u30f3\u30c8\u306f<strong>time(NULL)<\/strong>\u304c\u73fe\u5728\u306eUnix\u30bf\u30a4\u30e0\uff08\u30a8\u30dd\u30c3\u30af\u79d2\uff09\u3092\u8fd4\u3059\u305f\u3081\u3001\u5b9f\u884c\u306e\u305f\u3073\u306b\u7570\u306a\u308b\u5024\u306b\u306a\u308b\u3053\u3068\u3067\u3059\u3002<\/p>\n\n\n\n<div style=\"background:#f8f9fa;border-left:4px solid #6b7280;border-radius:0 8px 8px 0;padding:16px 20px;margin:20px 0;\">\n  <p style=\"margin:0 0 4px;font-size:13px;font-weight:700;color:#6b7280;letter-spacing:1px;\">&#128218; \u7528\u8a9e\u89e3\u8aac<\/p>\n  <p style=\"margin:0;font-size:15px;line-height:1.7;\"><strong>Unix\u30bf\u30a4\u30e0\uff08\u30a8\u30dd\u30c3\u30af\u79d2\uff09<\/strong>\uff1a1970\u5e741\u67081\u65e500:00:00 UTC \u3092\u57fa\u6e96\u306b\u3001\u7d4c\u904e\u3057\u305f\u79d2\u6570\u3092\u6574\u6570\u3067\u8868\u3057\u305f\u3082\u306e\u3002time(NULL)\u3092\u547c\u3076\u3068\u73fe\u5728\u306eUnix\u30bf\u30a4\u30e0\u304c\u8fd4\u308b\u30021\u79d2\u3054\u3068\u306b1\u305a\u3064\u5897\u3048\u308b\u305f\u3081\u3001\u7570\u306a\u308b\u79d2\u306b\u5b9f\u884c\u3059\u308b\u305f\u3073\u306b\u7570\u306a\u308b\u30b7\u30fc\u30c9\u306b\u306a\u308b\u3002<\/p>\n<\/div>\n\n\n\n<h3 class=\"wp-block-heading\">3-2. time.h\u306e\u30a4\u30f3\u30af\u30eb\u30fc\u30c9\u3092\u5fd8\u308c\u305a\u306b<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">time()\u95a2\u6570\u3092\u4f7f\u3046\u306b\u306f<code>&lt;time.h&gt;<\/code>\u306e\u30a4\u30f3\u30af\u30eb\u30fc\u30c9\u304c\u5fc5\u8981\u3067\u3059\u3002\u30a4\u30f3\u30af\u30eb\u30fc\u30c9\u305b\u305a\u306b\u4f7f\u3046\u3068\u300c\u6697\u9ed9\u306e\u95a2\u6570\u5ba3\u8a00\u300d\u8b66\u544a\u304c\u51fa\u308b\u304b\u3001\u8aa4\u3063\u305f\u578b\u3067\u30b7\u30fc\u30c9\u304c\u8a2d\u5b9a\u3055\u308c\u308b\u3053\u3068\u304c\u3042\u308a\u307e\u3059\u3002\u307e\u305f\u3001srand()\u306f\u30d7\u30ed\u30b0\u30e9\u30e0\u306e\u4e2d\u3067<strong>\u4e00\u5ea6\u3060\u3051\u547c\u3076<\/strong>\u306e\u304c\u6b63\u3057\u3044\u4f7f\u3044\u65b9\u3067\u3059\u3002\u30eb\u30fc\u30d7\u306e\u4e2d\u3067\u4f55\u5ea6\u3082\u547c\u3076\u306e\u306f\u5178\u578b\u7684\u306a\u30df\u30b9\u3067\u3059\uff08\u6b21\u7ae0\u3067\u8a73\u8ff0\uff09\u3002<\/p>\n\n\n\n<div style=\"background:#fafafa;border-radius:8px;padding:16px 20px;margin:16px 0;border-left:4px solid #dc2626;\">\n<div style=\"display:flex;align-items:flex-start;gap:8px;padding:6px 0;font-size:15px;line-height:1.6;\"><span style=\"color:#dc2626;font-size:16px;flex-shrink:0;margin-top:2px;\">&#10004;&#65039;<\/span><span><code>#include &lt;stdlib.h&gt;<\/code>: rand()\u3068srand()\u306e\u305f\u3081\u306b\u5fc5\u8981<\/span><\/div>\n<div style=\"display:flex;align-items:flex-start;gap:8px;padding:6px 0;font-size:15px;line-height:1.6;\"><span style=\"color:#dc2626;font-size:16px;flex-shrink:0;margin-top:2px;\">&#10004;&#65039;<\/span><span><code>#include &lt;time.h&gt;<\/code>: time()\u3092\u4f7f\u3046\u305f\u3081\u306b\u5fc5\u8981<\/span><\/div>\n<div style=\"display:flex;align-items:flex-start;gap:8px;padding:6px 0;font-size:15px;line-height:1.6;\"><span style=\"color:#dc2626;font-size:16px;flex-shrink:0;margin-top:2px;\">&#10004;&#65039;<\/span><span><code>srand((unsigned int)time(NULL))<\/code>: main\u95a2\u6570\u306e\u6700\u521d\u306b\u4e00\u5ea6\u3060\u3051\u547c\u3076<\/span><\/div>\n<div style=\"display:flex;align-items:flex-start;gap:8px;padding:6px 0;font-size:15px;line-height:1.6;\"><span style=\"color:#dc2626;font-size:16px;flex-shrink:0;margin-top:2px;\">&#10004;&#65039;<\/span><span>\u7b26\u53f7\u306a\u3057\u6574\u6570\u578b\uff08unsigned int\uff09\u3078\u306e\u30ad\u30e3\u30b9\u30c8\u3092\u5fd8\u308c\u306a\u3044<\/span><\/div>\n\n<\/div>\n\n\n\n<div class=\"balloon-wrap is-right\">\n  <div class=\"balloon-icon\">\n    <img decoding=\"async\" src=\"https:\/\/genai-ai.co.jp\/ai-kanri\/wp-content\/uploads\/2026\/04\/yamazaki-avatar.png\" alt=\"AI\u9b3c\u7ba1\u7406\u5c71\u5d0e\">\n    <span class=\"balloon-name\">AI\u9b3c\u7ba1\u7406\u5c71\u5d0e<\/span>\n  <\/div>\n  <div class=\"balloon-body\">srand(time(NULL))\u306e\u300c(unsigned int)\u300d\u3068\u3044\u3046\u30ad\u30e3\u30b9\u30c8\u304c\u3064\u3044\u3066\u3044\u308b\u306e\u306f\u3001time_t\u578b\uff08\u901a\u5e3864bit\u306e\u7b26\u53f7\u4ed8\u304d\u6574\u6570\uff09\u3092srand()\u304c\u53d7\u3051\u53d6\u308bunsigned int\u578b\u306b\u5909\u63db\u3059\u308b\u305f\u3081\u3067\u3059\u3002\u74b0\u5883\u306b\u3088\u3063\u3066\u306f\u30ad\u30e3\u30b9\u30c8\u306a\u3057\u3067\u3082\u52d5\u304d\u307e\u3059\u304c\u3001\u8b66\u544a\u3092\u51fa\u3055\u306a\u3044\u305f\u3081\u306b\u3082\u30ad\u30e3\u30b9\u30c8\u3092\u4ed8\u3051\u308b\u306e\u304c\u4f5c\u6cd5\u3067\u3059\u3002<\/div>\n<\/div>\n\n\n\n<h3 class=\"wp-block-heading\">3-3. \u540c\u3058\u30b7\u30fc\u30c9\u3092\u4f7f\u3063\u3066\u518d\u73fe\u53ef\u80fd\u306a\u30c6\u30b9\u30c8\u3092\u884c\u3046<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u30c6\u30b9\u30c8\u3084\u30c7\u30d0\u30c3\u30b0\u306e\u5834\u9762\u3067\u306f\u3001\u3042\u3048\u3066\u56fa\u5b9a\u306e\u30b7\u30fc\u30c9\u3092\u4f7f\u3046\u3053\u3068\u3067<strong>\u518d\u73fe\u53ef\u80fd\u306a\u4e71\u6570\u5217<\/strong>\u3092\u5f97\u308b\u5834\u5408\u3082\u3042\u308a\u307e\u3059\u3002\u3053\u308c\u306f\u30b2\u30fc\u30e0\u306e\u30ea\u30d7\u30ec\u30a4\u6a5f\u80fd\u3084\u3001\u30e9\u30f3\u30c0\u30e0\u8981\u7d20\u3092\u542b\u3080\u30a2\u30eb\u30b4\u30ea\u30ba\u30e0\u306e\u30c7\u30d0\u30c3\u30b0\u306b\u6d3b\u7528\u3055\u308c\u307e\u3059\u3002<\/p>\n\n\n\n<div style=\"background:#1e1e1e;border-radius:8px;padding:20px 24px;margin:20px 0;overflow-x:auto;\">\n  <pre style=\"margin:0;color:#d4d4d4;font-size:13px;line-height:1.8;font-family:'Consolas','Courier New',monospace;white-space:pre;\">#include <stdio.h>\n#include <stdlib.h>\n\nint main(void) {\n    int i;\n\n    \/* \u30b7\u30fc\u30c9=42\u3067\u56fa\u5b9a\uff08\u30c6\u30b9\u30c8\u30fb\u30c7\u30d0\u30c3\u30b0\u7528\uff09 *\/\n    srand(42);\n\n    printf(\"\u30b7\u30fc\u30c9=42\u3067\u306e\u4e71\u6570\u5217:\\n\");\n    for (i = 0; i < 5; i++) {\n        printf(\"  %d\\n\", rand());\n    }\n\n    \/* \u540c\u3058\u30b7\u30fc\u30c9\u3067\u30ea\u30bb\u30c3\u30c8 \u2192 \u540c\u3058\u6570\u5217\u304c\u518d\u73fe\u3055\u308c\u308b *\/\n    srand(42);\n    printf(\"\\n\u30b7\u30fc\u30c9=42\u3067\u30ea\u30bb\u30c3\u30c8\u5f8c\uff08\u540c\u3058\u6570\u5217\uff09:\\n\");\n    for (i = 0; i < 5; i++) {\n        printf(\"  %d\\n\", rand());\n    }\n\n    return 0;\n}<\/pre>\n<\/div>\n\n\n<div style=\"margin:48px 0 8px;display:flex;gap:12px;justify-content:center;flex-wrap:wrap;\"><a href=\"https:\/\/aikanri.genai-ai.co.jp\/seminar2-blog\/?utm_source=blog&#038;utm_medium=h2banner&#038;utm_content=cc-c-rand-random&#038;blog_slug=cc-c-rand-random\" target=\"_blank\" rel=\"noopener\" aria-label=\"Claude Code \u5b8c\u5168\u89e3\u8aac\u30bb\u30df\u30ca\u30fc\uff08\u7121\u6599\u30fb1on1\u30fb60\u5206\uff09\u306e\u4e88\u7d04\u753b\u9762\u3078\" style=\"flex:1 1 280px;max-width:360px;text-decoration:none;\"><img decoding=\"async\" src=\"https:\/\/genai-ai.co.jp\/ai-kanri\/wp-content\/uploads\/2026\/05\/cta_seminar_claude_code_2026.jpg\" alt=\"Claude Code \u5b8c\u5168\u89e3\u8aac\u30bb\u30df\u30ca\u30fc\uff5c\u7d4c\u55b6\u8005\u30fb\u4f1a\u793e\u5f79\u54e1\u5c02\u7528 1on1 60\u5206 \u7121\u6599\" style=\"width:100%;height:auto;border-radius:8px;display:block;\"><\/a><a href=\"https:\/\/aikanri.genai-ai.co.jp\/?utm_source=blog&#038;utm_medium=h2banner&#038;utm_campaign=cc-c-rand-random&#038;utm_content=h2-banner-kanri\" target=\"_blank\" rel=\"noopener\" aria-label=\"AI\u9b3c\u7ba1\u7406 \u516c\u5f0f\u30b5\u30a4\u30c8\u3078\" style=\"flex:1 1 280px;max-width:360px;text-decoration:none;\"><img decoding=\"async\" src=\"https:\/\/genai-ai.co.jp\/ai-kanri\/wp-content\/uploads\/2026\/05\/cta_blog_1to1.jpg\" alt=\"Claude Code\u3092\u7d4c\u55b6\u306b\u6d3b\u304b\u3057\u305f\u3044\u65b9\u3078 \u2014 AI\u9b3c\u7ba1\u7406\" style=\"width:100%;height:auto;border-radius:8px;display:block;\"><\/a><\/div>\n\n\n<div id=\"sec-04\"><\/div>\n<h2 class=\"section-header-img\" style=\"margin:32px 0 24px;border-radius:8px;overflow:hidden;background:linear-gradient(135deg,#1a1a1a 0%,#2a1015 100%);padding:32px 28px;color:#fff;position:relative;border:none;border-left:none;text-align:left;\">\n  <span class=\"section-number\" style=\"display:block;\">04<\/span>\n  <span class=\"section-label\" style=\"display:block;\">RANGE FORMULA<\/span>\n  <span class=\"section-title\" style=\"display:block;\">\u4e71\u6570\u306e\u7bc4\u56f2\u3092\u6307\u5b9a\u3059\u308b\u8a08\u7b97\u5f0f\u3092\u5b8c\u5168\u30de\u30b9\u30bf\u30fc<\/span>\n  <span class=\"section-desc\">1\u301c6\u30fb0\u301cN\u30fbn\u301cm\u306e\u5404\u30d1\u30bf\u30fc\u30f3\u3092\u516c\u5f0f\u3068\u4f8b\u3067\u5b8c\u5168\u7db2\u7f85<\/span>\n<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">rand()\u306f0\u301cRAND_MAX\u306e\u5024\u3092\u8fd4\u3057\u307e\u3059\u304c\u3001\u5b9f\u969b\u306b\u4f7f\u3044\u305f\u3044\u306e\u306f\u300c1\u301c6\uff08\u30b5\u30a4\u30b3\u30ed\uff09\u300d\u300c0\u301c99\uff08\u30d1\u30fc\u30bb\u30f3\u30c6\u30fc\u30b8\uff09\u300d\u300c50\u301c100\uff08\u7279\u5b9a\u7bc4\u56f2\uff09\u300d\u3068\u3044\u3063\u305f\u9650\u3089\u308c\u305f\u7bc4\u56f2\u306e\u5024\u3067\u3059\u3002\u3053\u306e\u7ae0\u3067\u306f\u3001<strong>\u4efb\u610f\u306e\u7bc4\u56f2\u3067\u4e71\u6570\u3092\u751f\u6210\u3059\u308b\u8a08\u7b97\u5f0f\u306e\u30d1\u30bf\u30fc\u30f3<\/strong>\u3092\u5b8c\u5168\u306b\u6574\u7406\u3057\u307e\u3059\u3002<\/p>\n\n\n\n<div class=\"point-box\">\n  <div class=\"point-title\">\u4e71\u6570\u7bc4\u56f2\u6307\u5b9a\u306e\u57fa\u672c\u516c\u5f0f\uff08\u5fc5\u305a\u899a\u3048\u308b\uff09<\/div>\n  <p><strong>n\u301cm \u306e\u4e71\u6570 = rand() % (m - n + 1) + n<\/strong><br><br>\u3053\u308c\u3060\u3051\u899a\u3048\u3066\u3044\u308c\u3070\u3001\u3042\u3089\u3086\u308b\u7bc4\u56f2\u306e\u4e71\u6570\u306b\u5bfe\u5fdc\u3067\u304d\u307e\u3059\u3002<br>\u4f8b: 1\u301c6 \u306e\u5834\u5408 \u2192 rand() % (6 - 1 + 1) + 1 = rand() % 6 + 1<\/p>\n<\/div>\n\n\n\n<h3 class=\"wp-block-heading\">4-1. \u3088\u304f\u4f7f\u3046\u30d1\u30bf\u30fc\u30f3\u5225\u306e\u8a08\u7b97\u5f0f\u4e00\u89a7<\/h3>\n\n\n\n<table>\n<thead><tr><th>\u7bc4\u56f2<\/th><th>\u8a08\u7b97\u5f0f<\/th><th>\u4f7f\u7528\u4f8b<\/th><\/tr><\/thead>\n<tbody>\n<tr><td>0 \u301c N-1<\/td><td>rand() % N<\/td><td>\u914d\u5217\u30a4\u30f3\u30c7\u30c3\u30af\u30b9 0\u301c(N-1)<\/td><\/tr>\n<tr><td>0 \u301c N<\/td><td>rand() % (N + 1)<\/td><td>0\u301cN\u306e\u6574\u6570<\/td><\/tr>\n<tr><td>1 \u301c N<\/td><td>rand() % N + 1<\/td><td>\u30b5\u30a4\u30b3\u30ed1\u301c6: rand()%6+1<\/td><\/tr>\n<tr><td>n \u301c m<\/td><td>rand() % (m - n + 1) + n<\/td><td>50\u301c100: rand()%51+50<\/td><\/tr>\n<tr><td>0.0 \u301c 1.0 (\u5c0f\u6570)<\/td><td>(double)rand() \/ RAND_MAX<\/td><td>\u78ba\u7387\u8a08\u7b97\u30fb\u6bd4\u7387<\/td><\/tr>\n<tr><td>0.0 \u301c N.0<\/td><td>(double)rand() \/ RAND_MAX * N<\/td><td>N\u4ee5\u4e0b\u306e\u5c0f\u6570<\/td><\/tr>\n<\/tbody>\n<\/table>\n\n\n\n<h3 class=\"wp-block-heading\">4-2. \u5404\u30d1\u30bf\u30fc\u30f3\u306e\u30b3\u30fc\u30c9\u4f8b<\/h3>\n\n\n\n<div style=\"background:#1e1e1e;border-radius:8px;padding:20px 24px;margin:20px 0;overflow-x:auto;\">\n  <pre style=\"margin:0;color:#d4d4d4;font-size:13px;line-height:1.8;font-family:'Consolas','Courier New',monospace;white-space:pre;\">#include <stdio.h>\n#include <stdlib.h>\n#include <time.h>\n\nint main(void) {\n    srand((unsigned int)time(NULL));\n\n    \/* \u30d1\u30bf\u30fc\u30f31: 0\u301cN-1 (\u914d\u5217\u30a4\u30f3\u30c7\u30c3\u30af\u30b9\u7528) *\/\n    int N = 10;\n    int idx = rand() % N;\n    printf(\"0\u301c9\u306e\u4e71\u6570: %d\\n\", idx);\n\n    \/* \u30d1\u30bf\u30fc\u30f32: 1\u301c6 (\u30b5\u30a4\u30b3\u30ed) *\/\n    int dice = rand() % 6 + 1;\n    printf(\"\u30b5\u30a4\u30b3\u30ed(1\u301c6): %d\\n\", dice);\n\n    \/* \u30d1\u30bf\u30fc\u30f33: 50\u301c100 *\/\n    int score = rand() % 51 + 50;\n    printf(\"50\u301c100\u306e\u4e71\u6570: %d\\n\", score);\n\n    \/* \u30d1\u30bf\u30fc\u30f34: -10\u301c10 (\u8ca0\u306e\u5024\u3092\u542b\u3080\u7bc4\u56f2) *\/\n    int signed_val = rand() % 21 - 10;\n    printf(\"-10\u301c10\u306e\u4e71\u6570: %d\\n\", signed_val);\n\n    \/* \u30d1\u30bf\u30fc\u30f35: 0.0\u301c1.0 \u306e\u5c0f\u6570 *\/\n    double prob = (double)rand() \/ RAND_MAX;\n    printf(\"0.0\u301c1.0\u306e\u78ba\u7387\u5024: %.4f\\n\", prob);\n\n    return 0;\n}<\/pre>\n<\/div>\n\n\n\n<div style=\"background:#f8f9fa;border-left:4px solid #6b7280;border-radius:0 8px 8px 0;padding:16px 20px;margin:20px 0;\">\n  <p style=\"margin:0 0 4px;font-size:13px;font-weight:700;color:#6b7280;letter-spacing:1px;\">&#128218; \u7528\u8a9e\u89e3\u8aac<\/p>\n  <p style=\"margin:0;font-size:15px;line-height:1.7;\"><strong>\u5270\u4f59\u6f14\u7b97\uff08%\u6f14\u7b97\u5b50\uff09<\/strong>\uff1aC\u306e%\u6f14\u7b97\u5b50\u306f\u300c\u5272\u308a\u7b97\u306e\u4f59\u308a\u300d\u3092\u8fd4\u3059\u3002rand()%6\u306f0\u301c5\u306e\u5024\u3092\u8fd4\u3059\uff086\u306e\u500d\u6570\u306e\u4f59\u308a\u306f0\u301c5\uff09\u3002+1\u3059\u308b\u3053\u3068\u30671\u301c6\u306b\u5909\u63db\u3067\u304d\u308b\u3002\u3053\u306e\u300c\u5270\u4f59+\u30aa\u30d5\u30bb\u30c3\u30c8\u300d\u30d1\u30bf\u30fc\u30f3\u304c\u4e71\u6570\u306e\u7bc4\u56f2\u6307\u5b9a\u306e\u6838\u5fc3\u3002<\/p>\n<\/div>\n\n\n\n<div style=\"background:#fef2f2;border:2px solid #dc2626;border-radius:8px;padding:20px 24px;margin:24px 0;\">\n  <div style=\"display:flex;align-items:center;gap:8px;margin-bottom:12px;\">\n    <span style=\"font-size:20px;\">&#9888;&#65039;<\/span>\n    <strong style=\"color:#dc2626;font-size:16px;\">\u5270\u4f59\u6cd5\u306e\u5206\u5e03\u306e\u504f\u308a\uff08\u4f4e\u54c1\u8cea\u306a\u4e00\u69d8\u6027\uff09\u306b\u6ce8\u610f<\/strong>\n  <\/div>\n  <p style=\"margin:0;font-size:15px;line-height:1.8;color:#333;\">rand() % N \u3068\u3044\u3046\u8a08\u7b97\u306f\u3001RAND_MAX\u304cN\u3067\u5272\u308a\u5207\u308c\u306a\u3044\u5834\u5408\u3001\u7279\u5b9a\u306e\u5024\u304c\u4ed6\u306e\u5024\u3088\u308a\u82e5\u5e72\u591a\u304f\u51fa\u73fe\u3059\u308b\u504f\u308a\u304c\u751f\u3058\u307e\u3059\u3002\u30b2\u30fc\u30e0\u306e\u52b9\u679c\u97f3\u30c8\u30ea\u30ac\u30fc\u3084\u7c21\u5358\u306a\u30b7\u30df\u30e5\u30ec\u30fc\u30b7\u30e7\u30f3\u3067\u306f\u554f\u984c\u3042\u308a\u307e\u305b\u3093\u304c\u3001\u7d71\u8a08\u7684\u306b\u53b3\u5bc6\u306a\u4e00\u69d8\u5206\u5e03\u304c\u5fc5\u8981\u306a\u5834\u5408\uff08\u7814\u7a76\u30fb\u6697\u53f7\u7b49\uff09\u306f\u3001\u5f8c\u8ff0\u306e\u3088\u308a\u826f\u3044\u4e71\u6570\u751f\u6210\u65b9\u6cd5\u3092\u4f7f\u3046\u5fc5\u8981\u304c\u3042\u308a\u307e\u3059\u3002<\/p>\n<\/div>\n\n\n\n<div class=\"balloon-wrap\">\n  <div class=\"balloon-icon\">\n    <img decoding=\"async\" src=\"https:\/\/genai-ai.co.jp\/ai-kanri\/wp-content\/uploads\/2026\/04\/ceo-sugasawa.jpg\" alt=\"\u4ee3\u8868\u83c5\u6fa4\">\n    <span class=\"balloon-name\">\u4ee3\u8868\u83c5\u6fa4<\/span>\n  <\/div>\n  <div class=\"balloon-body\">rand() % N \u306e\u504f\u308a\u554f\u984c\u306f\u7406\u8ad6\u7684\u306b\u306f\u5b58\u5728\u3057\u307e\u3059\u304c\u3001RAND_MAX\u304c\u5341\u5206\u5927\u304d\u3044\uff0820\u5104\u8d85\uff09\u5834\u5408\u3001\u5b9f\u7528\u4e0a\u306e\u5dee\u306f\u7121\u8996\u3067\u304d\u308b\u6c34\u6e96\u3067\u3059\u3002\u30b2\u30fc\u30e0\u3084\u5b66\u7fd2\u7528\u30d7\u30ed\u30b0\u30e9\u30e0\u306a\u3089\u6c17\u306b\u3059\u308b\u5fc5\u8981\u306f\u3042\u308a\u307e\u305b\u3093\u3002\u7d71\u8a08\u30fb\u6697\u53f7\u7528\u9014\u3067\u554f\u984c\u306b\u306a\u308b\u8a71\u3067\u3059\u3002<\/div>\n<\/div>\n\n\n<div style=\"margin:48px 0 8px;display:flex;gap:12px;justify-content:center;flex-wrap:wrap;\"><a href=\"https:\/\/aikanri.genai-ai.co.jp\/seminar2-blog\/?utm_source=blog&#038;utm_medium=h2banner&#038;utm_content=cc-c-rand-random&#038;blog_slug=cc-c-rand-random\" target=\"_blank\" rel=\"noopener\" aria-label=\"Claude Code \u5b8c\u5168\u89e3\u8aac\u30bb\u30df\u30ca\u30fc\uff08\u7121\u6599\u30fb1on1\u30fb60\u5206\uff09\u306e\u4e88\u7d04\u753b\u9762\u3078\" style=\"flex:1 1 280px;max-width:360px;text-decoration:none;\"><img decoding=\"async\" src=\"https:\/\/genai-ai.co.jp\/ai-kanri\/wp-content\/uploads\/2026\/05\/cta_seminar_claude_code_2026.jpg\" alt=\"Claude Code \u5b8c\u5168\u89e3\u8aac\u30bb\u30df\u30ca\u30fc\uff5c\u7d4c\u55b6\u8005\u30fb\u4f1a\u793e\u5f79\u54e1\u5c02\u7528 1on1 60\u5206 \u7121\u6599\" style=\"width:100%;height:auto;border-radius:8px;display:block;\"><\/a><a href=\"https:\/\/aikanri.genai-ai.co.jp\/?utm_source=blog&#038;utm_medium=h2banner&#038;utm_campaign=cc-c-rand-random&#038;utm_content=h2-banner-kanri\" target=\"_blank\" rel=\"noopener\" aria-label=\"AI\u9b3c\u7ba1\u7406 \u516c\u5f0f\u30b5\u30a4\u30c8\u3078\" style=\"flex:1 1 280px;max-width:360px;text-decoration:none;\"><img decoding=\"async\" src=\"https:\/\/genai-ai.co.jp\/ai-kanri\/wp-content\/uploads\/2026\/05\/cta_blog_1to1.jpg\" alt=\"Claude Code\u3092\u7d4c\u55b6\u306b\u6d3b\u304b\u3057\u305f\u3044\u65b9\u3078 \u2014 AI\u9b3c\u7ba1\u7406\" style=\"width:100%;height:auto;border-radius:8px;display:block;\"><\/a><\/div>\n\n\n<div id=\"sec-05\"><\/div>\n<h2 class=\"section-header-img\" style=\"margin:32px 0 24px;border-radius:8px;overflow:hidden;background:linear-gradient(135deg,#1a1a1a 0%,#2a1015 100%);padding:32px 28px;color:#fff;position:relative;border:none;border-left:none;text-align:left;\">\n  <span class=\"section-number\" style=\"display:block;\">05<\/span>\n  <span class=\"section-label\" style=\"display:block;\">SAMPLE CODE<\/span>\n  <span class=\"section-title\" style=\"display:block;\">\u5b9f\u8df5\u30b5\u30f3\u30d7\u30eb\u30b3\u30fc\u30c9\u96c6\uff1a\u30b5\u30a4\u30b3\u30ed\u30fb\u3058\u3083\u3093\u3051\u3093\u30fb\u914d\u5217\u30b7\u30e3\u30c3\u30d5\u30eb<\/span>\n  <span class=\"section-desc\">\u30b3\u30d4\u30fc&\u30da\u30fc\u30b9\u30c8\u3067\u4f7f\u3048\u308b\u5b8c\u5168\u52d5\u4f5c\u30b5\u30f3\u30d7\u30eb7\u672c<\/span>\n<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u3053\u3053\u307e\u3067\u5b66\u3093\u3060\u77e5\u8b58\u3092\u6d3b\u304b\u3057\u3066\u3001\u5b9f\u969b\u306b\u52d5\u304f\u5b9f\u8df5\u30b5\u30f3\u30d7\u30eb\u30927\u672c\u7d39\u4ecb\u3057\u307e\u3059\u3002\u5b66\u7fd2\u306e\u6bb5\u968e\u306b\u5408\u308f\u305b\u3066\u53c2\u7167\u30fb\u6539\u9020\u3057\u3066\u304f\u3060\u3055\u3044\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">5-1. \u30b5\u30a4\u30b3\u30ed\u30b7\u30df\u30e5\u30ec\u30fc\u30b7\u30e7\u30f3<\/h3>\n\n\n\n<div style=\"background:#1e1e1e;border-radius:8px;padding:20px 24px;margin:20px 0;overflow-x:auto;\">\n  <pre style=\"margin:0;color:#d4d4d4;font-size:13px;line-height:1.8;font-family:'Consolas','Courier New',monospace;white-space:pre;\">#include <stdio.h>\n#include <stdlib.h>\n#include <time.h>\n\nint main(void) {\n    int i, dice;\n    srand((unsigned int)time(NULL));\n\n    printf(\"=== \u30b5\u30a4\u30b3\u30ed\u30b7\u30df\u30e5\u30ec\u30fc\u30b7\u30e7\u30f3\uff0810\u56de\uff09 ===\\n\");\n    for (i = 0; i < 10; i++) {\n        dice = rand() % 6 + 1;\n        printf(\"\u7b2c%2d\u56de: %d\\n\", i + 1, dice);\n    }\n    return 0;\n}<\/pre>\n<\/div>\n\n\n\n<h3 class=\"wp-block-heading\">5-2. \u3058\u3083\u3093\u3051\u3093\u30b2\u30fc\u30e0<\/h3>\n\n\n\n<div style=\"background:#1e1e1e;border-radius:8px;padding:20px 24px;margin:20px 0;overflow-x:auto;\">\n  <pre style=\"margin:0;color:#d4d4d4;font-size:13px;line-height:1.8;font-family:'Consolas','Courier New',monospace;white-space:pre;\">#include <stdio.h>\n#include <stdlib.h>\n#include <time.h>\n\nint main(void) {\n    const char *hands[] = {\"\u30b0\u30fc\", \"\u30c1\u30e7\u30ad\", \"\u30d1\u30fc\"};\n    int player_input, com_hand;\n\n    srand((unsigned int)time(NULL));\n\n    printf(\"\u3058\u3083\u3093\u3051\u3093\u30b2\u30fc\u30e0\uff080=\u30b0\u30fc, 1=\u30c1\u30e7\u30ad, 2=\u30d1\u30fc\uff09\\n\");\n    printf(\"\u3042\u306a\u305f\u306e\u624b\u3092\u5165\u529b: \");\n    scanf(\"%d\", &player_input);\n\n    if (player_input < 0 || player_input > 2) {\n        printf(\"\u7121\u52b9\u306a\u5165\u529b\u3067\u3059\\n\");\n        return 1;\n    }\n\n    com_hand = rand() % 3;\n    printf(\"\u3042\u306a\u305f: %s\\n\", hands[player_input]);\n    printf(\"\u30b3\u30f3\u30d4\u30e5\u30fc\u30bf: %s\\n\", hands[com_hand]);\n\n    if (player_input == com_hand) {\n        printf(\"\u7d50\u679c: \u5f15\u304d\u5206\u3051\\n\");\n    } else if ((player_input + 1) % 3 == com_hand) {\n        printf(\"\u7d50\u679c: \u3042\u306a\u305f\u306e\u8ca0\u3051\\n\");\n    } else {\n        printf(\"\u7d50\u679c: \u3042\u306a\u305f\u306e\u52dd\u3061\\n\");\n    }\n\n    return 0;\n}<\/pre>\n<\/div>\n\n\n\n<h3 class=\"wp-block-heading\">5-3. \u914d\u5217\u306e\u30e9\u30f3\u30c0\u30e0\u30b7\u30e3\u30c3\u30d5\u30eb\uff08Fisher-Yates\u30a2\u30eb\u30b4\u30ea\u30ba\u30e0\uff09<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u914d\u5217\u306e\u8981\u7d20\u3092\u30e9\u30f3\u30c0\u30e0\u306b\u4e26\u3073\u66ff\u3048\u308b\u300c\u30b7\u30e3\u30c3\u30d5\u30eb\u300d\u306f\u3001\u30b2\u30fc\u30e0\u306e\u5c71\u672d\u30fb\u30af\u30a4\u30ba\u306e\u9078\u629e\u80a2\u9806\u5e8f\u306a\u3069\u3067\u983b\u7e41\u306b\u5fc5\u8981\u306b\u306a\u308a\u307e\u3059\u3002\u6700\u3082\u54c1\u8cea\u306e\u9ad8\u3044\u30b7\u30e3\u30c3\u30d5\u30eb\u30a2\u30eb\u30b4\u30ea\u30ba\u30e0\u306fFisher-Yates\u30a2\u30eb\u30b4\u30ea\u30ba\u30e0\u3067\u3059\u3002<\/p>\n\n\n\n<div style=\"background:#f8f9fa;border-left:4px solid #6b7280;border-radius:0 8px 8px 0;padding:16px 20px;margin:20px 0;\">\n  <p style=\"margin:0 0 4px;font-size:13px;font-weight:700;color:#6b7280;letter-spacing:1px;\">&#128218; \u7528\u8a9e\u89e3\u8aac<\/p>\n  <p style=\"margin:0;font-size:15px;line-height:1.7;\"><strong>Fisher-Yates\u30a2\u30eb\u30b4\u30ea\u30ba\u30e0<\/strong>\uff1a\u914d\u5217\u3092\u30e9\u30f3\u30c0\u30e0\u306b\u30b7\u30e3\u30c3\u30d5\u30eb\u3059\u308b\u6700\u3082\u6709\u540d\u3067\u54c1\u8cea\u306e\u9ad8\u3044\u30a2\u30eb\u30b4\u30ea\u30ba\u30e0\u3002\u672b\u5c3e\u304b\u3089\u5148\u982d\u306b\u5411\u304b\u3063\u3066\u3001\u5404\u8981\u7d20\u3092\u305d\u308c\u4ee5\u524d\u306e\u30e9\u30f3\u30c0\u30e0\u306a\u4f4d\u7f6e\u306e\u8981\u7d20\u3068\u5165\u308c\u66ff\u3048\u308b\u3002\u8a08\u7b97\u91cfO(n)\u3067\u3001\u5168\u3066\u306e\u9806\u5217\u304c\u7b49\u78ba\u7387\u3067\u73fe\u308c\u308b\u3053\u3068\u304c\u4fdd\u8a3c\u3055\u308c\u3066\u3044\u308b\u3002\u30b2\u30fc\u30e0\u306e\u5c71\u672d\u30b7\u30e3\u30c3\u30d5\u30eb\u3084\u554f\u984c\u306e\u9806\u5e8f\u30e9\u30f3\u30c0\u30e0\u5316\u306b\u4f7f\u308f\u308c\u308b\u3002<\/p>\n<\/div>\n\n\n\n<div style=\"background:#1e1e1e;border-radius:8px;padding:20px 24px;margin:20px 0;overflow-x:auto;\">\n  <pre style=\"margin:0;color:#d4d4d4;font-size:13px;line-height:1.8;font-family:'Consolas','Courier New',monospace;white-space:pre;\">#include <stdio.h>\n#include <stdlib.h>\n#include <time.h>\n\n\/* Fisher-Yates\u30a2\u30eb\u30b4\u30ea\u30ba\u30e0\u3067\u914d\u5217\u3092\u30b7\u30e3\u30c3\u30d5\u30eb *\/\nvoid shuffle(int *arr, int n) {\n    int i, j, temp;\n    for (i = n - 1; i > 0; i--) {\n        j = rand() % (i + 1);   \/* 0\u301ci \u306e\u30e9\u30f3\u30c0\u30e0\u30a4\u30f3\u30c7\u30c3\u30af\u30b9 *\/\n        temp = arr[i];\n        arr[i] = arr[j];\n        arr[j] = temp;\n    }\n}\n\nint main(void) {\n    int i;\n    int deck[13] = {1,2,3,4,5,6,7,8,9,10,11,12,13}; \/* \u30c8\u30e9\u30f3\u30d7\u306e1\u301c13 *\/\n\n    srand((unsigned int)time(NULL));\n\n    printf(\"\u30b7\u30e3\u30c3\u30d5\u30eb\u524d: \");\n    for (i = 0; i < 13; i++) printf(\"%d \", deck[i]);\n    printf(\"\\n\");\n\n    shuffle(deck, 13);\n\n    printf(\"\u30b7\u30e3\u30c3\u30d5\u30eb\u5f8c: \");\n    for (i = 0; i < 13; i++) printf(\"%d \", deck[i]);\n    printf(\"\\n\");\n\n    return 0;\n}<\/pre>\n<\/div>\n\n\n\n<h3 class=\"wp-block-heading\">5-4. \u4e71\u6570\u306e\u7d71\u8a08\u691c\u8a3c\uff08\u5206\u5e03\u306e\u78ba\u8a8d\uff09<\/h3>\n\n\n\n<div style=\"background:#1e1e1e;border-radius:8px;padding:20px 24px;margin:20px 0;overflow-x:auto;\">\n  <pre style=\"margin:0;color:#d4d4d4;font-size:13px;line-height:1.8;font-family:'Consolas','Courier New',monospace;white-space:pre;\">#include <stdio.h>\n#include <stdlib.h>\n#include <time.h>\n\nint main(void) {\n    int i, val;\n    int count[6] = {0};   \/* 1\u301c6\u306e\u51fa\u73fe\u56de\u6570 *\/\n    int TRIALS = 60000;   \/* \u8a66\u884c\u56de\u6570 *\/\n\n    srand((unsigned int)time(NULL));\n\n    \/* 60000\u56de\u30b5\u30a4\u30b3\u30ed\u3092\u632f\u308b *\/\n    for (i = 0; i < TRIALS; i++) {\n        val = rand() % 6;   \/* 0\u301c5 *\/\n        count[val]++;\n    }\n\n    printf(\"=== \u30b5\u30a4\u30b3\u30ed %d \u56de\u306e\u7d71\u8a08 ===\\n\", TRIALS);\n    for (i = 0; i < 6; i++) {\n        printf(\"%d \u306e\u76ee: %5d \u56de (%.1f%%)\\n\",\n               i + 1, count[i], (double)count[i] \/ TRIALS * 100);\n    }\n\n    return 0;\n}<\/pre>\n<\/div>\n\n\n\n<div style=\"background:#f0fdf4;border:1px solid #22c55e;border-radius:8px;padding:20px 24px;margin:24px 0;\">\n  <div style=\"display:flex;align-items:center;gap:8px;margin-bottom:12px;\">\n    <span style=\"font-size:18px;\">&#128161;<\/span>\n    <strong style=\"color:#16a34a;font-size:15px;\">\u7d71\u8a08\u691c\u8a3c\u3067\u4e00\u69d8\u5206\u5e03\u3092\u78ba\u8a8d\u3059\u308b<\/strong>\n  <\/div>\n  <p style=\"margin:0;font-size:15px;line-height:1.8;color:#333;\">\u4e0a\u306e\u30b3\u30fc\u30c9\u3067\u5404\u76ee\u304c16.6%\u524d\u5f8c\uff08= 100%\u00f76\uff09\u3067\u3042\u308c\u3070\u3001rand()\u304c\u4e00\u69d8\u306b\u5206\u5e03\u3057\u3066\u3044\u308b\u3053\u3068\u304c\u78ba\u8a8d\u3067\u304d\u307e\u3059\u3002\u5927\u5e45\u306b\u504f\u308a\u304c\u51fa\u308b\u5834\u5408\u306f\u3001\u30b3\u30f3\u30d1\u30a4\u30e9\u30fb\u74b0\u5883\u30fbrand()\u306e\u5b9f\u88c5\u54c1\u8cea\u3092\u7591\u3046\u5fc5\u8981\u304c\u3042\u308a\u307e\u3059\u3002<\/p>\n<\/div>\n\n\n\n<div class=\"balloon-wrap is-right\">\n  <div class=\"balloon-icon\">\n    <img decoding=\"async\" src=\"https:\/\/genai-ai.co.jp\/ai-kanri\/wp-content\/uploads\/2026\/04\/yamazaki-avatar.png\" alt=\"AI\u9b3c\u7ba1\u7406\u5c71\u5d0e\">\n    <span class=\"balloon-name\">AI\u9b3c\u7ba1\u7406\u5c71\u5d0e<\/span>\n  <\/div>\n  <div class=\"balloon-body\">Fisher-Yates\u30a2\u30eb\u30b4\u30ea\u30ba\u30e0\u306f\u300c\u5168\u3066\u306e\u9806\u5217\u304c\u7b49\u78ba\u7387\u3067\u73fe\u308c\u308b\u300d\u3053\u3068\u304c\u6570\u5b66\u7684\u306b\u8a3c\u660e\u3055\u308c\u3066\u3044\u308b\u65b9\u6cd5\u3067\u3059\u3002\u3088\u304f\u3042\u308b\u8aa4\u5b9f\u88c5\u300crand()\u3067\u30a4\u30f3\u30c7\u30c3\u30af\u30b9\u30922\u3064\u9078\u3093\u3067\u4ea4\u63db\u3092\u7e70\u308a\u8fd4\u3059\u300d\u3067\u306f\u504f\u308a\u304c\u51fa\u308b\u305f\u3081\u3001\u30b2\u30fc\u30e0\u958b\u767a\u3084\u516c\u5e73\u6027\u304c\u5fc5\u8981\u306a\u30b7\u30b9\u30c6\u30e0\u3067\u306f\u5fc5\u305aFisher-Yates\u3092\u4f7f\u3063\u3066\u304f\u3060\u3055\u3044\u3002<\/div>\n<\/div>\n\n\n<div style=\"margin:48px 0 8px;display:flex;gap:12px;justify-content:center;flex-wrap:wrap;\"><a href=\"https:\/\/aikanri.genai-ai.co.jp\/seminar2-blog\/?utm_source=blog&#038;utm_medium=h2banner&#038;utm_content=cc-c-rand-random&#038;blog_slug=cc-c-rand-random\" target=\"_blank\" rel=\"noopener\" aria-label=\"Claude Code \u5b8c\u5168\u89e3\u8aac\u30bb\u30df\u30ca\u30fc\uff08\u7121\u6599\u30fb1on1\u30fb60\u5206\uff09\u306e\u4e88\u7d04\u753b\u9762\u3078\" style=\"flex:1 1 280px;max-width:360px;text-decoration:none;\"><img decoding=\"async\" src=\"https:\/\/genai-ai.co.jp\/ai-kanri\/wp-content\/uploads\/2026\/05\/cta_seminar_claude_code_2026.jpg\" alt=\"Claude Code \u5b8c\u5168\u89e3\u8aac\u30bb\u30df\u30ca\u30fc\uff5c\u7d4c\u55b6\u8005\u30fb\u4f1a\u793e\u5f79\u54e1\u5c02\u7528 1on1 60\u5206 \u7121\u6599\" style=\"width:100%;height:auto;border-radius:8px;display:block;\"><\/a><a href=\"https:\/\/aikanri.genai-ai.co.jp\/?utm_source=blog&#038;utm_medium=h2banner&#038;utm_campaign=cc-c-rand-random&#038;utm_content=h2-banner-kanri\" target=\"_blank\" rel=\"noopener\" aria-label=\"AI\u9b3c\u7ba1\u7406 \u516c\u5f0f\u30b5\u30a4\u30c8\u3078\" style=\"flex:1 1 280px;max-width:360px;text-decoration:none;\"><img decoding=\"async\" src=\"https:\/\/genai-ai.co.jp\/ai-kanri\/wp-content\/uploads\/2026\/05\/cta_blog_1to1.jpg\" alt=\"Claude Code\u3092\u7d4c\u55b6\u306b\u6d3b\u304b\u3057\u305f\u3044\u65b9\u3078 \u2014 AI\u9b3c\u7ba1\u7406\" style=\"width:100%;height:auto;border-radius:8px;display:block;\"><\/a><\/div>\n\n\n<div id=\"sec-06\"><\/div>\n<h2 class=\"section-header-img\" style=\"margin:32px 0 24px;border-radius:8px;overflow:hidden;background:linear-gradient(135deg,#1a1a1a 0%,#2a1015 100%);padding:32px 28px;color:#fff;position:relative;border:none;border-left:none;text-align:left;\">\n  <span class=\"section-number\" style=\"display:block;\">06<\/span>\n  <span class=\"section-label\" style=\"display:block;\">COMMON MISTAKES<\/span>\n  <span class=\"section-title\" style=\"display:block;\">\u3088\u304f\u3042\u308b\u30df\u30b9\u3068\u843d\u3068\u3057\u7a74\uff1a\u521d\u5b66\u8005\u304c\u5fc5\u305a\u30cf\u30de\u308b\u30dd\u30a4\u30f3\u30c8<\/span>\n  <span class=\"section-desc\">\u5178\u578b\u7684\u306a5\u3064\u306e\u30d0\u30b0\u30d1\u30bf\u30fc\u30f3\u3068\u305d\u306e\u4fee\u6b63\u65b9\u6cd5<\/span>\n<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">C\u8a00\u8a9e\u306e\u4e71\u6570\u306f\u300c\u57fa\u672c\u306f\u30b7\u30f3\u30d7\u30eb\u300d\u306a\u306e\u306b\u3001\u5b9f\u969b\u306b\u30b3\u30fc\u30c9\u3092\u66f8\u304f\u3068\u4e88\u671f\u3057\u306a\u3044\u52d5\u4f5c\u306b\u51fa\u4f1a\u3044\u3084\u3059\u3044\u9818\u57df\u3067\u3059\u3002\u4ee5\u4e0b\u306b\u3001\u521d\u5b66\u8005\u304c\u5fc5\u305a\u3068\u3044\u3063\u3066\u3044\u3044\u307b\u3069\u30cf\u30de\u308b<strong>5\u3064\u306e\u3088\u304f\u3042\u308b\u30df\u30b9<\/strong>\u3092\u30d1\u30bf\u30fc\u30f3\u5225\u306b\u89e3\u8aac\u3057\u307e\u3059\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">\u30df\u30b91: srand()\u3092\u30eb\u30fc\u30d7\u306e\u4e2d\u3067\u547c\u3076<\/h3>\n\n\n\n<div style=\"background:#fef2f2;border:2px solid #dc2626;border-radius:8px;padding:20px 24px;margin:24px 0;\">\n  <div style=\"display:flex;align-items:center;gap:8px;margin-bottom:12px;\">\n    <span style=\"font-size:20px;\">&#9888;&#65039;<\/span>\n    <strong style=\"color:#dc2626;font-size:16px;\">\u30eb\u30fc\u30d7\u5185\u3067srand(time(NULL))\u3092\u547c\u3076\u306e\u306f\u6700\u3082\u5178\u578b\u7684\u306a\u8aa4\u308a<\/strong>\n  <\/div>\n  <p style=\"margin:0;font-size:15px;line-height:1.8;color:#333;\">\u30eb\u30fc\u30d7\u304c1\u79d2\u4ee5\u5185\u306b\u5b8c\u4e86\u3059\u308b\u5834\u5408\u3001time(NULL)\u306e\u5024\u304c\u5909\u5316\u3057\u306a\u3044\u305f\u3081\u540c\u3058\u30b7\u30fc\u30c9\u2192\u540c\u3058\u4e71\u6570\u304c\u6bce\u56de\u8fd4\u308a\u307e\u3059\u3002srand()\u306fmain\u95a2\u6570\u306e\u5148\u982d\u3067\u4e00\u5ea6\u3060\u3051\u547c\u3076\u306e\u304c\u6b63\u3057\u3044\u3002<\/p>\n<\/div>\n\n\n\n<div style=\"background:#1e1e1e;border-radius:8px;padding:20px 24px;margin:20px 0;overflow-x:auto;\">\n  <pre style=\"margin:0;color:#d4d4d4;font-size:13px;line-height:1.8;font-family:'Consolas','Courier New',monospace;white-space:pre;\">\/* NG\u4f8b\uff1a\u30eb\u30fc\u30d7\u5185\u3067srand\u3092\u547c\u3076 \u2192 \u6bce\u56de\u540c\u3058\u6570\u304c\u8fd4\u308b *\/\nfor (i = 0; i < 5; i++) {\n    srand((unsigned int)time(NULL));  \/* \u2190 \u3053\u3053\u304cNG *\/\n    printf(\"%d\\n\", rand());\n}\n\n\/* OK\u4f8b\uff1amain\u95a2\u6570\u306e\u5148\u982d\u3067\u4e00\u5ea6\u3060\u3051\u547c\u3076 *\/\nsrand((unsigned int)time(NULL));     \/* \u2190 \u3053\u3053\u3067\u4e00\u5ea6\u3060\u3051 *\/\nfor (i = 0; i < 5; i++) {\n    printf(\"%d\\n\", rand());\n}<\/pre>\n<\/div>\n\n\n\n<h3 class=\"wp-block-heading\">\u30df\u30b92: stdlib.h\u3092\u30a4\u30f3\u30af\u30eb\u30fc\u30c9\u3057\u306a\u3044<\/h3>\n\n\n\n<div style=\"background:#1e1e1e;border-radius:8px;padding:20px 24px;margin:20px 0;overflow-x:auto;\">\n  <pre style=\"margin:0;color:#d4d4d4;font-size:13px;line-height:1.8;font-family:'Consolas','Courier New',monospace;white-space:pre;\">\/* NG\u4f8b\uff1a\u30d8\u30c3\u30c0\u306a\u3057\uff08\u30b3\u30f3\u30d1\u30a4\u30eb\u8b66\u544a\u307e\u305f\u306f\u30a8\u30e9\u30fc\uff09 *\/\nint x = rand();   \/* stdlib.h\u3092\u30a4\u30f3\u30af\u30eb\u30fc\u30c9\u3057\u3066\u3044\u306a\u3044 *\/\n\n\/* OK\u4f8b *\/\n#include <stdlib.h>\nint x = rand();   \/* \u6b63\u3057\u304f\u52d5\u4f5c\u3059\u308b *\/<\/pre>\n<\/div>\n\n\n\n<h3 class=\"wp-block-heading\">\u30df\u30b93: rand()\u306e\u623b\u308a\u5024\u306e\u578b\u3092\u8aa4\u89e3\u3059\u308b<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">rand()\u306fint\u578b\uff08\u7b26\u53f7\u4ed8\u304d\u6574\u6570\uff09\u3092\u8fd4\u3057\u307e\u3059\u3002<strong>double\u578b\u306b\u76f4\u63a5\u4ee3\u5165\u3059\u308b\u3068\u7cbe\u5ea6\u304c\u4e0b\u304c\u308b\u5834\u5408<\/strong>\u304c\u3042\u308b\u305f\u3081\u3001\u5c0f\u6570\u306e\u4e71\u6570\u304c\u5fc5\u8981\u306a\u3068\u304d\u306f\u660e\u793a\u7684\u306b\u30ad\u30e3\u30b9\u30c8\u304c\u5fc5\u8981\u3067\u3059\u3002<\/p>\n\n\n\n<div style=\"background:#1e1e1e;border-radius:8px;padding:20px 24px;margin:20px 0;overflow-x:auto;\">\n  <pre style=\"margin:0;color:#d4d4d4;font-size:13px;line-height:1.8;font-family:'Consolas','Courier New',monospace;white-space:pre;\">\/* NG\u4f8b\uff1adouble\u3078\u306e\u76f4\u63a5\u4ee3\u5165\uff08\u7cbe\u5ea6\u306e\u554f\u984c\uff09 *\/\ndouble r = rand() \/ RAND_MAX;   \/* \u6574\u6570\u9664\u7b97\u306b\u306a\u3063\u3066\u5e38\u306b0.0\uff01 *\/\n\n\/* OK\u4f8b\uff1adouble\u306b\u30ad\u30e3\u30b9\u30c8\u3057\u3066\u304b\u3089\u9664\u7b97 *\/\ndouble r = (double)rand() \/ RAND_MAX;   \/* 0.0\u301c1.0 \u306e\u5c0f\u6570 *\/<\/pre>\n<\/div>\n\n\n\n<h3 class=\"wp-block-heading\">\u30df\u30b94: \u7bc4\u56f2\u6307\u5b9a\u306e\u8a08\u7b97\u5f0f\u306e\u30aa\u30d5\u30df\u30b9\u30a8\u30e9\u30fc<\/h3>\n\n\n\n<div style=\"background:#1e1e1e;border-radius:8px;padding:20px 24px;margin:20px 0;overflow-x:auto;\">\n  <pre style=\"margin:0;color:#d4d4d4;font-size:13px;line-height:1.8;font-family:'Consolas','Courier New',monospace;white-space:pre;\">\/* NG\u4f8b\uff1a1\u301c6\u306e\u3064\u3082\u308a\u304c0\u301c5\u306b\u306a\u308b *\/\nint dice = rand() % 6;      \/* 0\u301c5 \u2190 \u9593\u9055\u3044 *\/\n\n\/* OK\u4f8b\uff1a1\u301c6\u306e\u6b63\u3057\u3044\u8a08\u7b97 *\/\nint dice = rand() % 6 + 1;  \/* 1\u301c6 \u2190 \u6b63\u3057\u3044 *\/\n\n\/* NG\u4f8b\uff1a1\u301c100\u306e\u3064\u3082\u308a\u304c0\u301c99\u306b\u306a\u308b *\/\nint pct = rand() % 100;     \/* 0\u301c99 \u2190 100\u306f\u51fa\u306a\u3044 *\/\n\n\/* OK\u4f8b\uff1a1\u301c100 *\/\nint pct = rand() % 100 + 1; \/* 1\u301c100 \u2190 \u6b63\u3057\u3044 *\/<\/pre>\n<\/div>\n\n\n\n<h3 class=\"wp-block-heading\">\u30df\u30b95: time.h\u3092\u30a4\u30f3\u30af\u30eb\u30fc\u30c9\u305b\u305a\u306btime()\u3092\u4f7f\u3046<\/h3>\n\n\n\n<div style=\"background:#1e1e1e;border-radius:8px;padding:20px 24px;margin:20px 0;overflow-x:auto;\">\n  <pre style=\"margin:0;color:#d4d4d4;font-size:13px;line-height:1.8;font-family:'Consolas','Courier New',monospace;white-space:pre;\">\/* NG\u4f8b\uff1atime.h\u306a\u3057 *\/\nsrand(time(NULL));   \/* time()\u304c\u672a\u5b9a\u7fa9\u306e\u305f\u3081\u30a8\u30e9\u30fc\u307e\u305f\u306f\u8b66\u544a *\/\n\n\/* OK\u4f8b *\/\n#include <time.h>\nsrand((unsigned int)time(NULL));  \/* \u6b63\u3057\u304f\u52d5\u4f5c\u3059\u308b *\/<\/pre>\n<\/div>\n\n\n\n<div style=\"background:#fafafa;border-radius:8px;padding:16px 20px;margin:16px 0;border-left:4px solid #dc2626;\">\n<div style=\"display:flex;align-items:flex-start;gap:8px;padding:6px 0;font-size:15px;line-height:1.6;\"><span style=\"color:#dc2626;font-size:16px;flex-shrink:0;margin-top:2px;\">&#10004;&#65039;<\/span><span>srand()\u306fmain()\u306e\u5148\u982d\u3067<strong>\u4e00\u5ea6\u3060\u3051<\/strong>\u547c\u3076<\/span><\/div>\n<div style=\"display:flex;align-items:flex-start;gap:8px;padding:6px 0;font-size:15px;line-height:1.6;\"><span style=\"color:#dc2626;font-size:16px;flex-shrink:0;margin-top:2px;\">&#10004;&#65039;<\/span><span><code>#include &lt;stdlib.h&gt;<\/code>\u3068<code>#include &lt;time.h&gt;<\/code>\u306e\u4e21\u65b9\u3092\u5fd8\u308c\u305a\u306b<\/span><\/div>\n<div style=\"display:flex;align-items:flex-start;gap:8px;padding:6px 0;font-size:15px;line-height:1.6;\"><span style=\"color:#dc2626;font-size:16px;flex-shrink:0;margin-top:2px;\">&#10004;&#65039;<\/span><span>0.0\u301c1.0\u306e\u5c0f\u6570\u4e71\u6570\u306f <code>(double)rand() \/ RAND_MAX<\/code>\uff08\u30ad\u30e3\u30b9\u30c8\u304c\u5fc5\u8981\uff09<\/span><\/div>\n<div style=\"display:flex;align-items:flex-start;gap:8px;padding:6px 0;font-size:15px;line-height:1.6;\"><span style=\"color:#dc2626;font-size:16px;flex-shrink:0;margin-top:2px;\">&#10004;&#65039;<\/span><span>1\u301cN \u306e\u4e71\u6570\u306f <code>rand() % N + 1<\/code>\uff08+1\u3092\u5fd8\u308c\u306a\u3044\uff09<\/span><\/div>\n<div style=\"display:flex;align-items:flex-start;gap:8px;padding:6px 0;font-size:15px;line-height:1.6;\"><span style=\"color:#dc2626;font-size:16px;flex-shrink:0;margin-top:2px;\">&#10004;&#65039;<\/span><span>n\u301cm \u306e\u4e71\u6570\u306f <code>rand() % (m-n+1) + n<\/code><\/span><\/div>\n\n<\/div>\n\n\n<div style=\"margin:48px 0 8px;display:flex;gap:12px;justify-content:center;flex-wrap:wrap;\"><a href=\"https:\/\/aikanri.genai-ai.co.jp\/seminar2-blog\/?utm_source=blog&#038;utm_medium=h2banner&#038;utm_content=cc-c-rand-random&#038;blog_slug=cc-c-rand-random\" target=\"_blank\" rel=\"noopener\" aria-label=\"Claude Code \u5b8c\u5168\u89e3\u8aac\u30bb\u30df\u30ca\u30fc\uff08\u7121\u6599\u30fb1on1\u30fb60\u5206\uff09\u306e\u4e88\u7d04\u753b\u9762\u3078\" style=\"flex:1 1 280px;max-width:360px;text-decoration:none;\"><img decoding=\"async\" src=\"https:\/\/genai-ai.co.jp\/ai-kanri\/wp-content\/uploads\/2026\/05\/cta_seminar_claude_code_2026.jpg\" alt=\"Claude Code \u5b8c\u5168\u89e3\u8aac\u30bb\u30df\u30ca\u30fc\uff5c\u7d4c\u55b6\u8005\u30fb\u4f1a\u793e\u5f79\u54e1\u5c02\u7528 1on1 60\u5206 \u7121\u6599\" style=\"width:100%;height:auto;border-radius:8px;display:block;\"><\/a><a href=\"https:\/\/aikanri.genai-ai.co.jp\/?utm_source=blog&#038;utm_medium=h2banner&#038;utm_campaign=cc-c-rand-random&#038;utm_content=h2-banner-kanri\" target=\"_blank\" rel=\"noopener\" aria-label=\"AI\u9b3c\u7ba1\u7406 \u516c\u5f0f\u30b5\u30a4\u30c8\u3078\" style=\"flex:1 1 280px;max-width:360px;text-decoration:none;\"><img decoding=\"async\" src=\"https:\/\/genai-ai.co.jp\/ai-kanri\/wp-content\/uploads\/2026\/05\/cta_blog_1to1.jpg\" alt=\"Claude Code\u3092\u7d4c\u55b6\u306b\u6d3b\u304b\u3057\u305f\u3044\u65b9\u3078 \u2014 AI\u9b3c\u7ba1\u7406\" style=\"width:100%;height:auto;border-radius:8px;display:block;\"><\/a><\/div>\n\n\n<div id=\"sec-07\"><\/div>\n<h2 class=\"section-header-img\" style=\"margin:32px 0 24px;border-radius:8px;overflow:hidden;background:linear-gradient(135deg,#1a1a1a 0%,#2a1015 100%);padding:32px 28px;color:#fff;position:relative;border:none;border-left:none;text-align:left;\">\n  <span class=\"section-number\" style=\"display:block;\">07<\/span>\n  <span class=\"section-label\" style=\"display:block;\">ADVANCED<\/span>\n  <span class=\"section-title\" style=\"display:block;\">\u767a\u5c55\uff1a\u3088\u308a\u826f\u3044\u4e71\u6570\u751f\u6210\u306e\u9078\u629e\u80a2<\/span>\n  <span class=\"section-desc\">rand()\u306e\u9650\u754c\u3092\u8d85\u3048\u308b\u30e1\u30eb\u30bb\u30f3\u30cc\u30c4\u30a4\u30b9\u30bf\u30fc\u3068OS\u63d0\u4f9b\u306e\u4e71\u6570<\/span>\n<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">C\u8a00\u8a9e\u306e\u6a19\u6e96rand()\u306f\u5b66\u7fd2\u30fb\u7c21\u6613\u30b2\u30fc\u30e0\u306b\u306f\u5341\u5206\u3067\u3059\u304c\u3001<strong>\u7d71\u8a08\u30b7\u30df\u30e5\u30ec\u30fc\u30b7\u30e7\u30f3\u30fb\u30bb\u30ad\u30e5\u30ea\u30c6\u30a3\u30fb\u5927\u898f\u6a21\u4e71\u6570\u751f\u6210<\/strong>\u3067\u306f\u54c1\u8cea\u304c\u4e0d\u5341\u5206\u306a\u5834\u5408\u304c\u3042\u308a\u307e\u3059\u3002\u3053\u3053\u3067\u306f\u3001\u3088\u308a\u54c1\u8cea\u306e\u9ad8\u3044\u4e71\u6570\u751f\u6210\u306e\u9078\u629e\u80a2\u3092\u7d39\u4ecb\u3057\u307e\u3059\u3002<\/p>\n\n\n\n<table>\n<thead><tr><th>\u4e71\u6570\u751f\u6210\u65b9\u6cd5<\/th><th>\u54c1\u8cea<\/th><th>\u901f\u5ea6<\/th><th>\u4e3b\u306a\u7528\u9014<\/th><th>\u79fb\u690d\u6027<\/th><\/tr><\/thead>\n<tbody>\n<tr><td>rand()\uff08C\u6a19\u6e96\uff09<\/td><td>\u4f4e\u301c\u4e2d<\/td><td>\u9ad8\u901f<\/td><td>\u5b66\u7fd2\u30fb\u7c21\u6613\u30b2\u30fc\u30e0<\/td><td>\u25ce\uff08ANSI C\uff09<\/td><\/tr>\n<tr><td>\u30e1\u30eb\u30bb\u30f3\u30cc\u30c4\u30a4\u30b9\u30bf\u30fc\uff08MT19937\uff09<\/td><td>\u9ad8<\/td><td>\u9ad8\u901f<\/td><td>\u30b7\u30df\u30e5\u30ec\u30fc\u30b7\u30e7\u30f3\u30fb\u30b2\u30fc\u30e0<\/td><td>\u25cb\uff08\u5916\u90e8\u5b9f\u88c5\u304c\u5fc5\u8981\uff09<\/td><\/tr>\n<tr><td>\/dev\/urandom\uff08Linux\/macOS\uff09<\/td><td>\u6700\u9ad8\uff08\u771f\u4e71\u6570\u5bc4\u308a\uff09<\/td><td>\u3084\u3084\u9045\u3044<\/td><td>\u6697\u53f7\u9375\u30fb\u30bb\u30ad\u30e5\u30ea\u30c6\u30a3<\/td><td>\u00d7\uff08Unix\u7cfb\u306e\u307f\uff09<\/td><\/tr>\n<tr><td>arc4random()\uff08BSD\u7cfb\uff09<\/td><td>\u9ad8<\/td><td>\u9ad8\u901f<\/td><td>\u30bb\u30ad\u30e5\u30ea\u30c6\u30a3\u91cd\u8996<\/td><td>\u25b3\uff08Unix\u7cfb\uff09<\/td><\/tr>\n<tr><td>C++11\u306emt19937<\/td><td>\u9ad8<\/td><td>\u9ad8\u901f<\/td><td>C++\u3067\u306e\u30b7\u30df\u30e5\u30ec\u30fc\u30b7\u30e7\u30f3<\/td><td>\u25cb\uff08C++11\u4ee5\u4e0a\uff09<\/td><\/tr>\n<\/tbody>\n<\/table>\n\n\n\n<div style=\"background:#f8f9fa;border-left:4px solid #6b7280;border-radius:0 8px 8px 0;padding:16px 20px;margin:20px 0;\">\n  <p style=\"margin:0 0 4px;font-size:13px;font-weight:700;color:#6b7280;letter-spacing:1px;\">&#128218; \u7528\u8a9e\u89e3\u8aac<\/p>\n  <p style=\"margin:0;font-size:15px;line-height:1.7;\"><strong>\u30e1\u30eb\u30bb\u30f3\u30cc\u30c4\u30a4\u30b9\u30bf\u30fc\uff08MT19937\uff09<\/strong>\uff1a1997\u5e74\u306b\u677e\u672c\u771e\u30fb\u897f\u6751\u62d3\u58eb\u304c\u8003\u6848\u3057\u305f\u7591\u4f3c\u4e71\u6570\u751f\u6210\u30a2\u30eb\u30b4\u30ea\u30ba\u30e0\u3002\u5468\u671f\u304c2^19937-1\u3068\u3044\u3046\u5929\u6587\u5b66\u7684\u306b\u9577\u304f\u3001\u7d71\u8a08\u7684\u54c1\u8cea\u3082\u6975\u3081\u3066\u9ad8\u3044\u3002rand()\u3068\u7570\u306a\u308a\u5916\u90e8\u5b9f\u88c5\uff08\u30d8\u30c3\u30c0\u30d5\u30a1\u30a4\u30eb\uff09\u304c\u5fc5\u8981\u3060\u304c\u3001\u30b2\u30fc\u30e0\u958b\u767a\u30fb\u30e2\u30f3\u30c6\u30ab\u30eb\u30ed\u30b7\u30df\u30e5\u30ec\u30fc\u30b7\u30e7\u30f3\u30fb\u6a5f\u68b0\u5b66\u7fd2\u3067\u306e\u30e9\u30f3\u30c0\u30e0\u521d\u671f\u5316\u306a\u3069\u306b\u5e83\u304f\u4f7f\u308f\u308c\u308b\u3002<\/p>\n<\/div>\n\n\n\n<div style=\"background:#f0fdf4;border:1px solid #22c55e;border-radius:8px;padding:20px 24px;margin:24px 0;\">\n  <div style=\"display:flex;align-items:center;gap:8px;margin-bottom:12px;\">\n    <span style=\"font-size:18px;\">&#128161;<\/span>\n    <strong style=\"color:#16a34a;font-size:15px;\">\u30bb\u30ad\u30e5\u30ea\u30c6\u30a3\u7528\u9014\u306b\u306f\u7d76\u5bfe\u306brand()\u3092\u4f7f\u308f\u306a\u3044<\/strong>\n  <\/div>\n  <p style=\"margin:0;font-size:15px;line-height:1.8;color:#333;\">\u4e71\u6570\u3092\u6697\u53f7\u9375\u30fb\u30c8\u30fc\u30af\u30f3\u30fb\u30d1\u30b9\u30ef\u30fc\u30c9\u751f\u6210\u306b\u4f7f\u3046\u5834\u5408\u306f\u3001\u7d76\u5bfe\u306brand()\u3092\u4f7f\u3063\u3066\u306f\u3044\u3051\u307e\u305b\u3093\u3002rand()\u306f\u7591\u4f3c\u4e71\u6570\u3067\u3042\u308a\u3001\u30b7\u30fc\u30c9\u3068\u51fa\u529b\u304b\u3089\u6b21\u306e\u5024\u304c\u4e88\u6e2c\u53ef\u80fd\u3067\u3059\u3002Linux\u306a\u3089 getrandom() \u3084 \/dev\/urandom\u3001Windows\u306a\u3089 BCryptGenRandom() \u306a\u3069OS\u304c\u63d0\u4f9b\u3059\u308b\u30bb\u30ad\u30e5\u30ea\u30c6\u30a3\u7528\u4e71\u6570API\u3092\u4f7f\u3063\u3066\u304f\u3060\u3055\u3044\u3002<\/p>\n<\/div>\n\n\n\n<div class=\"g-flow-row\" style=\"margin:24px 0;\">\n  <div class=\"g-flow-item\"><strong>\u7528\u9014\u3092\u78ba\u8a8d<\/strong><br><span style=\"font-size:12px;\">\u5b66\u7fd2\/\u30b2\u30fc\u30e0\/\u7d71\u8a08<br>\/\u30bb\u30ad\u30e5\u30ea\u30c6\u30a3<br>\u3069\u308c\u304b\uff1f<\/span><\/div>\n  <div class=\"g-flow-arrow\">&#8594;<\/div>\n  <div class=\"g-flow-item\"><strong>\u4e71\u6570\u54c1\u8cea\u3092\u9078\u629e<\/strong><br><span style=\"font-size:12px;\">\u5b66\u7fd2\u2192rand()<br>\u30b7\u30df\u30e5\u30ec\u30fc\u30b7\u30e7\u30f3\u2192MT<br>\u6697\u53f7\u2192OS API<\/span><\/div>\n  <div class=\"g-flow-arrow\">&#8594;<\/div>\n  <div class=\"g-flow-item\"><strong>\u521d\u671f\u5316\u65b9\u6cd5\u3092\u6c7a\u3081\u308b<\/strong><br><span style=\"font-size:12px;\">rand\u2192srand(time)<br>MT\u2192\u9069\u5207\u306a\u7a2e<br>OS\u2192\u4e0d\u8981<\/span><\/div>\n  <div class=\"g-flow-arrow\">&#8594;<\/div>\n  <div class=\"g-flow-item\"><strong>\u7bc4\u56f2\u6307\u5b9a\u3057\u3066\u4f7f\u7528<\/strong><br><span style=\"font-size:12px;\">rand() % N + n<br>\u306e\u30d1\u30bf\u30fc\u30f3\u3092\u9069\u7528<\/span><\/div>\n<\/div>\n\n\n\n<div class=\"balloon-wrap\">\n  <div class=\"balloon-icon\">\n    <img decoding=\"async\" src=\"https:\/\/genai-ai.co.jp\/ai-kanri\/wp-content\/uploads\/2026\/04\/ceo-sugasawa.jpg\" alt=\"\u4ee3\u8868\u83c5\u6fa4\">\n    <span class=\"balloon-name\">\u4ee3\u8868\u83c5\u6fa4<\/span>\n  <\/div>\n  <div class=\"balloon-body\">\u30b2\u30fc\u30e0\u30fb\u30b7\u30df\u30e5\u30ec\u30fc\u30b7\u30e7\u30f3\u30fb\u6a5f\u68b0\u5b66\u7fd2\u3067C\/C++\u3092\u4f7f\u3046\u5834\u5408\u3001\u30e1\u30eb\u30bb\u30f3\u30cc\u30c4\u30a4\u30b9\u30bf\u30fc\u306f\u5b9a\u756a\u306e\u9078\u629e\u80a2\u3067\u3059\u3002C++\u306a\u3089std::mt19937\u304c\u6a19\u6e96\u30e9\u30a4\u30d6\u30e9\u30ea\u306b\u542b\u307e\u308c\u3066\u3044\u308b\u306e\u3067\u3001\u30d8\u30c3\u30c0\u5b9f\u88c5\u3082\u4e0d\u8981\u3067\u3059\u3002C\u8a00\u8a9e\u306e\u5834\u5408\u306f\u3001\u516c\u5f0f\u30b5\u30a4\u30c8\u3067\u516c\u958b\u3055\u308c\u3066\u3044\u308bmt19937.c\u3092\u7d44\u307f\u8fbc\u3080\u65b9\u6cd5\u304c\u4e00\u822c\u7684\u3067\u3059\u3002<\/div>\n<\/div>\n\n\n<div style=\"margin:48px 0 8px;display:flex;gap:12px;justify-content:center;flex-wrap:wrap;\"><a href=\"https:\/\/aikanri.genai-ai.co.jp\/seminar2-blog\/?utm_source=blog&#038;utm_medium=h2banner&#038;utm_content=cc-c-rand-random&#038;blog_slug=cc-c-rand-random\" target=\"_blank\" rel=\"noopener\" aria-label=\"Claude Code \u5b8c\u5168\u89e3\u8aac\u30bb\u30df\u30ca\u30fc\uff08\u7121\u6599\u30fb1on1\u30fb60\u5206\uff09\u306e\u4e88\u7d04\u753b\u9762\u3078\" style=\"flex:1 1 280px;max-width:360px;text-decoration:none;\"><img decoding=\"async\" src=\"https:\/\/genai-ai.co.jp\/ai-kanri\/wp-content\/uploads\/2026\/05\/cta_seminar_claude_code_2026.jpg\" alt=\"Claude Code \u5b8c\u5168\u89e3\u8aac\u30bb\u30df\u30ca\u30fc\uff5c\u7d4c\u55b6\u8005\u30fb\u4f1a\u793e\u5f79\u54e1\u5c02\u7528 1on1 60\u5206 \u7121\u6599\" style=\"width:100%;height:auto;border-radius:8px;display:block;\"><\/a><a href=\"https:\/\/aikanri.genai-ai.co.jp\/?utm_source=blog&#038;utm_medium=h2banner&#038;utm_campaign=cc-c-rand-random&#038;utm_content=h2-banner-kanri\" target=\"_blank\" rel=\"noopener\" aria-label=\"AI\u9b3c\u7ba1\u7406 \u516c\u5f0f\u30b5\u30a4\u30c8\u3078\" style=\"flex:1 1 280px;max-width:360px;text-decoration:none;\"><img decoding=\"async\" src=\"https:\/\/genai-ai.co.jp\/ai-kanri\/wp-content\/uploads\/2026\/05\/cta_blog_1to1.jpg\" alt=\"Claude Code\u3092\u7d4c\u55b6\u306b\u6d3b\u304b\u3057\u305f\u3044\u65b9\u3078 \u2014 AI\u9b3c\u7ba1\u7406\" style=\"width:100%;height:auto;border-radius:8px;display:block;\"><\/a><\/div>\n\n\n<div id=\"sec-08\"><\/div>\n<h2 class=\"section-header-img\" style=\"margin:32px 0 24px;border-radius:8px;overflow:hidden;background:linear-gradient(135deg,#1a1a1a 0%,#2a1015 100%);padding:32px 28px;color:#fff;position:relative;border:none;border-left:none;text-align:left;\">\n  <span class=\"section-number\" style=\"display:block;\">08<\/span>\n  <span class=\"section-label\" style=\"display:block;\">AI CODING<\/span>\n  <span class=\"section-title\" style=\"display:block;\">Claude Code\u3067C\u8a00\u8a9e\u30b3\u30fc\u30c9\u3092\u81ea\u52d5\u751f\u6210\u3059\u308b<\/span>\n  <span class=\"section-desc\">\u30d7\u30ed\u30f3\u30d7\u30c8\u4e00\u3064\u3067\u5b8c\u52d5\u3059\u308bC\u30b3\u30fc\u30c9\u3092\u6570\u79d2\u3067\u5f97\u308b\u65b9\u6cd5<\/span>\n<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">C\u8a00\u8a9e\u306e\u4e71\u6570\u51e6\u7406\u306f\u6b63\u78ba\u306a\u77e5\u8b58\u304c\u5fc5\u8981\u3067\u3001\u521d\u5fc3\u8005\u304c\u72ec\u529b\u3067\u66f8\u304f\u3068\u30d0\u30b0\u3092\u8e0f\u307f\u3084\u3059\u3044\u9818\u57df\u3067\u3059\u3002\u3053\u306e\u554f\u984c\u3092\u89e3\u6c7a\u3059\u308b\u4e00\u3064\u306e\u9078\u629e\u80a2\u3068\u3057\u3066\u3001<strong>Claude Code\u3092\u4f7f\u3063\u305fC\u8a00\u8a9e\u30b3\u30fc\u30c9\u306e\u81ea\u52d5\u751f\u6210<\/strong>\u304c\u3042\u308a\u307e\u3059\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Claude Code\u306f\u3001\u65e5\u672c\u8a9e\u306e\u6307\u793a\u6587\u3092\u5165\u529b\u3059\u308b\u3060\u3051\u3067\u3001\u5b8c\u5168\u306b\u52d5\u4f5c\u3059\u308bC\u8a00\u8a9e\u306e\u30b3\u30fc\u30c9\u3092\u751f\u6210\u3057\u3066\u304f\u308c\u307e\u3059\u3002<strong>\u300csrand(time(NULL))\u306e\u521d\u671f\u5316\u3092\u542b\u3081\u3066\u300d\u300c\u30a8\u30e9\u30fc\u30cf\u30f3\u30c9\u30ea\u30f3\u30b0\u4ed8\u304d\u3067\u300d\u300c\u30b3\u30e1\u30f3\u30c8\u3092\u65e5\u672c\u8a9e\u3067\u300d<\/strong>\u3068\u3044\u3063\u305f\u7d30\u304b\u3044\u8981\u4ef6\u3082\u65e5\u672c\u8a9e\u3067\u4f1d\u3048\u3089\u308c\u308b\u305f\u3081\u3001C\u8a00\u8a9e\u306b\u6163\u308c\u3066\u3044\u306a\u3044\u6bb5\u968e\u3067\u3082\u5b9f\u7528\u7684\u306a\u30b3\u30fc\u30c9\u304c\u5f97\u3089\u308c\u307e\u3059\u3002<\/p>\n\n\n\n<table>\n<thead><tr><th>\u3084\u308a\u305f\u3044\u3053\u3068<\/th><th>Claude Code\u3078\u306e\u30d7\u30ed\u30f3\u30d7\u30c8\u4f8b<\/th><\/tr><\/thead>\n<tbody>\n<tr><td>\u30b5\u30a4\u30b3\u30ed\u30b7\u30df\u30e5\u30ec\u30fc\u30b7\u30e7\u30f3<\/td><td>\u300cC\u8a00\u8a9e\u3067\u3001srand(time(NULL))\u3067\u521d\u671f\u5316\u3057\u3066\u30011\u301c6\u306e\u30b5\u30a4\u30b3\u30ed\u309210\u56de\u632f\u3063\u3066\u7d50\u679c\u3068\u7d71\u8a08\uff08\u5404\u76ee\u306e\u51fa\u73fe\u7387\uff09\u3092\u8868\u793a\u3059\u308b\u30d7\u30ed\u30b0\u30e9\u30e0\u3092\u66f8\u3044\u3066\u3002\u65e5\u672c\u8a9e\u30b3\u30e1\u30f3\u30c8\u4ed8\u304d\u3067\u300d<\/td><\/tr>\n<tr><td>\u3058\u3083\u3093\u3051\u3093\u30b2\u30fc\u30e0<\/td><td>\u300cC\u8a00\u8a9e\u3067\u3058\u3083\u3093\u3051\u3093\u30b2\u30fc\u30e0\u3092\u4f5c\u3063\u3066\u3002\u30d7\u30ec\u30a4\u30e4\u30fc\u304c0\/1\/2\u3067\u30b0\u30fc\/\u30c1\u30e7\u30ad\/\u30d1\u30fc\u3092\u5165\u529b\u3057\u3001CPU\u306frand()\u3067\u30e9\u30f3\u30c0\u30e0\u306b\u9078\u3076\u3002\u52dd\u6557\u5224\u5b9a\u3092\u8868\u793a\u3002\u5165\u529b\u30d0\u30ea\u30c7\u30fc\u30b7\u30e7\u30f3\u4ed8\u304d\u300d<\/td><\/tr>\n<tr><td>\u914d\u5217\u30b7\u30e3\u30c3\u30d5\u30eb<\/td><td>\u300cC\u8a00\u8a9e\u3067Fisher-Yates\u30a2\u30eb\u30b4\u30ea\u30ba\u30e0\u3092\u4f7f\u3063\u3066\u6574\u6570\u914d\u5217\u3092\u30b7\u30e3\u30c3\u30d5\u30eb\u3059\u308b\u95a2\u6570\u3092\u66f8\u3044\u3066\u3002\u5f15\u6570\u306f\u914d\u5217\u30dd\u30a4\u30f3\u30bf\u3068\u8981\u7d20\u6570\u3002\u4f7f\u7528\u4f8b\u306emain\u95a2\u6570\u3082\u4ed8\u3051\u3066\u300d<\/td><\/tr>\n<tr><td>\u4e71\u6570\u306e\u7bc4\u56f2\u6307\u5b9a<\/td><td>\u300cC\u8a00\u8a9e\u3067n\u301cm\u306e\u7bc4\u56f2\u306e\u4e71\u6570\u3092\u751f\u6210\u3059\u308b\u95a2\u6570random_in_range(int n, int m)\u3092\u66f8\u3044\u3066\u3002srand\u521d\u671f\u5316\u306fmain\u3067\u3057\u3066\u3042\u308b\u524d\u63d0\u3067\u3002\u4f7f\u7528\u4f8b\u3082\u4ed8\u3051\u3066\u300d<\/td><\/tr>\n<\/tbody>\n<\/table>\n\n\n\n<h3 class=\"wp-block-heading\">8-1. Claude Code\u3092\u4f7f\u3046\u30d5\u30ed\u30fc<\/h3>\n\n\n\n<div class=\"g-flow-row\" style=\"margin:24px 0;\">\n  <div class=\"g-flow-item\"><strong>\u8981\u4ef6\u3092\u6574\u7406\u3059\u308b<\/strong><br><span style=\"font-size:12px;\">\u4f55\u3092\u30fb\u3069\u306e\u7bc4\u56f2\u3067<br>\u30fb\u3069\u3093\u306a\u6a5f\u80fd\u304c<br>\u5fc5\u8981\u304b\u8a00\u8a9e\u5316<\/span><\/div>\n  <div class=\"g-flow-arrow\">&#8594;<\/div>\n  <div class=\"g-flow-item\"><strong>Claude Code\u306b\u6307\u793a<\/strong><br><span style=\"font-size:12px;\">\u65e5\u672c\u8a9e\u3067\u8981\u4ef6\u3092<br>\u30c6\u30ad\u30b9\u30c8\u5165\u529b\u3059\u308b<br>\uff08\u8a73\u7d30\u306b\u66f8\u304f\u307b\u3069\u826f\u3044\uff09<\/span><\/div>\n  <div class=\"g-flow-arrow\">&#8594;<\/div>\n  <div class=\"g-flow-item\"><strong>\u30b3\u30fc\u30c9\u3092\u53d7\u3051\u53d6\u308b<\/strong><br><span style=\"font-size:12px;\">\u6570\u79d2\u3067\u5b8c\u52d5C\u30b3\u30fc\u30c9\u304c<br>\u751f\u6210\u3055\u308c\u308b<br>\u8ffd\u52a0\u6307\u793a\u3082\u53ef\u80fd<\/span><\/div>\n  <div class=\"g-flow-arrow\">&#8594;<\/div>\n  <div class=\"g-flow-item\"><strong>\u30b3\u30f3\u30d1\u30a4\u30eb\u30fb\u52d5\u4f5c\u78ba\u8a8d<\/strong><br><span style=\"font-size:12px;\">gcc\u3067\u30d3\u30eb\u30c9\u3057\u3066<br>\u52d5\u4f5c\u3092\u78ba\u8a8d\u3002<br>\u4fee\u6b63\u306f\u518d\u6307\u793a<\/span><\/div>\n<\/div>\n\n\n\n<div style=\"background:#f0fdf4;border:1px solid #22c55e;border-radius:8px;padding:20px 24px;margin:24px 0;\">\n  <div style=\"display:flex;align-items:center;gap:8px;margin-bottom:12px;\">\n    <span style=\"font-size:18px;\">&#128161;<\/span>\n    <strong style=\"color:#16a34a;font-size:15px;\">\u30a8\u30e9\u30fc\u30e1\u30c3\u30bb\u30fc\u30b8\u3092\u305d\u306e\u307e\u307eClaude Code\u306b\u8cbc\u308a\u4ed8\u3051\u308b\u3068\u4fee\u6b63\u3057\u3066\u304f\u308c\u308b<\/strong>\n  <\/div>\n  <p style=\"margin:0;font-size:15px;line-height:1.8;color:#333;\">\u30b3\u30f3\u30d1\u30a4\u30eb\u30a8\u30e9\u30fc\u3084\u5b9f\u884c\u6642\u30a8\u30e9\u30fc\u304c\u51fa\u305f\u5834\u5408\u3001\u30a8\u30e9\u30fc\u30e1\u30c3\u30bb\u30fc\u30b8\u3068\u30bd\u30fc\u30b9\u30b3\u30fc\u30c9\u3092Claude Code\u306b\u305d\u306e\u307e\u307e\u8cbc\u308a\u4ed8\u3051\u3066\u300c\u3053\u306e\u30a8\u30e9\u30fc\u3092\u76f4\u3057\u3066\u300d\u3068\u4f1d\u3048\u308b\u3060\u3051\u3067\u4fee\u6b63\u6848\u304c\u8fd4\u3063\u3066\u304d\u307e\u3059\u3002C\u8a00\u8a9e\u306e\u5178\u578b\u30a8\u30e9\u30fc\uff08\u30bb\u30b0\u30e1\u30f3\u30c6\u30fc\u30b7\u30e7\u30f3\u9055\u53cd\u30fb\u578b\u4e0d\u4e00\u81f4\u30fb\u672a\u521d\u671f\u5316\u5909\u6570\u7b49\uff09\u3078\u306e\u5bfe\u51e6\u3082\u307b\u307c1\u767a\u3067\u89e3\u6c7a\u3067\u304d\u307e\u3059\u3002<\/p>\n<\/div>\n\n\n\n<div class=\"balloon-wrap is-right\">\n  <div class=\"balloon-icon\">\n    <img decoding=\"async\" src=\"https:\/\/genai-ai.co.jp\/ai-kanri\/wp-content\/uploads\/2026\/04\/yamazaki-avatar.png\" alt=\"AI\u9b3c\u7ba1\u7406\u5c71\u5d0e\">\n    <span class=\"balloon-name\">AI\u9b3c\u7ba1\u7406\u5c71\u5d0e<\/span>\n  <\/div>\n  <div class=\"balloon-body\">C\u8a00\u8a9e\u306e\u4e71\u6570\u30b3\u30fc\u30c9\u306f\u300c\u52d5\u304b\u3057\u65b9\u306f\u308f\u304b\u3063\u305f\u3001\u3067\u3082\u30d0\u30b0\u306e\u539f\u56e0\u304c\u308f\u304b\u3089\u306a\u3044\u300d\u3068\u306a\u308a\u304c\u3061\u3067\u3059\u3002\u305d\u3046\u3044\u3046\u3068\u304dClaude Code\u306b\u300c\u3053\u306e\u30b3\u30fc\u30c9\u3067\u30e9\u30f3\u30c0\u30e0\u306a\u5024\u304c\u51fa\u306a\u3044\u7406\u7531\u3092\u8abf\u3079\u3066\u300d\u3068\u6295\u3052\u308b\u3068\u3001srand()\u306e\u4f4d\u7f6e\u30fb\u578b\u306e\u30df\u30b9\u30fb\u30d8\u30c3\u30c0\u306e\u6f0f\u308c\u306a\u3069\u3092\u4e00\u6c17\u306b\u8a3a\u65ad\u3057\u3066\u304f\u308c\u307e\u3059\u3002<\/div>\n<\/div>\n\n\n<div style=\"margin:48px 0 8px;display:flex;gap:12px;justify-content:center;flex-wrap:wrap;\"><a href=\"https:\/\/aikanri.genai-ai.co.jp\/seminar2-blog\/?utm_source=blog&#038;utm_medium=h2banner&#038;utm_content=cc-c-rand-random&#038;blog_slug=cc-c-rand-random\" target=\"_blank\" rel=\"noopener\" aria-label=\"Claude Code \u5b8c\u5168\u89e3\u8aac\u30bb\u30df\u30ca\u30fc\uff08\u7121\u6599\u30fb1on1\u30fb60\u5206\uff09\u306e\u4e88\u7d04\u753b\u9762\u3078\" style=\"flex:1 1 280px;max-width:360px;text-decoration:none;\"><img decoding=\"async\" src=\"https:\/\/genai-ai.co.jp\/ai-kanri\/wp-content\/uploads\/2026\/05\/cta_seminar_claude_code_2026.jpg\" alt=\"Claude Code \u5b8c\u5168\u89e3\u8aac\u30bb\u30df\u30ca\u30fc\uff5c\u7d4c\u55b6\u8005\u30fb\u4f1a\u793e\u5f79\u54e1\u5c02\u7528 1on1 60\u5206 \u7121\u6599\" style=\"width:100%;height:auto;border-radius:8px;display:block;\"><\/a><a href=\"https:\/\/aikanri.genai-ai.co.jp\/?utm_source=blog&#038;utm_medium=h2banner&#038;utm_campaign=cc-c-rand-random&#038;utm_content=h2-banner-kanri\" target=\"_blank\" rel=\"noopener\" aria-label=\"AI\u9b3c\u7ba1\u7406 \u516c\u5f0f\u30b5\u30a4\u30c8\u3078\" style=\"flex:1 1 280px;max-width:360px;text-decoration:none;\"><img decoding=\"async\" src=\"https:\/\/genai-ai.co.jp\/ai-kanri\/wp-content\/uploads\/2026\/05\/cta_blog_1to1.jpg\" alt=\"Claude Code\u3092\u7d4c\u55b6\u306b\u6d3b\u304b\u3057\u305f\u3044\u65b9\u3078 \u2014 AI\u9b3c\u7ba1\u7406\" style=\"width:100%;height:auto;border-radius:8px;display:block;\"><\/a><\/div>\n\n\n<div id=\"sec-09\"><\/div>\n<h2 class=\"section-header-img\" style=\"margin:32px 0 24px;border-radius:8px;overflow:hidden;background:linear-gradient(135deg,#1a1a1a 0%,#2a1015 100%);padding:32px 28px;color:#fff;position:relative;border:none;border-left:none;text-align:left;\">\n  <span class=\"section-number\" style=\"display:block;\">09<\/span>\n  <span class=\"section-label\" style=\"display:block;\">CONCLUSION<\/span>\n  <span class=\"section-title\" style=\"display:block;\">\u307e\u3068\u3081\uff1aC\u8a00\u8a9e\u306e\u4e71\u6570\u3092\u30de\u30b9\u30bf\u30fc\u3059\u308b\u305f\u3081\u306e\u30ed\u30fc\u30c9\u30de\u30c3\u30d7<\/span>\n  <span class=\"section-desc\">\u5b66\u7fd2\u306e\u6b21\u306e\u30b9\u30c6\u30c3\u30d7\u3068AI\u3092\u6d3b\u7528\u3057\u305f\u52b9\u7387\u5316\u306e\u65b9\u5411\u6027<\/span>\n<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u3053\u306e\u8a18\u4e8b\u3067\u306f\u3001C\u8a00\u8a9e\u306erand()\/srand()\u3092\u4f7f\u3063\u305f\u4e71\u6570\u751f\u6210\u3092\u57fa\u790e\u304b\u3089\u767a\u5c55\u307e\u3067\u4f53\u7cfb\u7684\u306b\u89e3\u8aac\u3057\u307e\u3057\u305f\u3002<\/p>\n\n\n\n<div style=\"background:#fafafa;border-radius:8px;padding:16px 20px;margin:16px 0;border-left:4px solid #dc2626;\">\n<div style=\"display:flex;align-items:flex-start;gap:8px;padding:6px 0;font-size:15px;line-height:1.6;\"><span style=\"color:#dc2626;font-size:16px;flex-shrink:0;margin-top:2px;\">&#10004;&#65039;<\/span><span>\u4e71\u6570\u306b\u306f<strong>\u771f\u306e\u4e71\u6570\u3068\u7591\u4f3c\u4e71\u6570<\/strong>\u304c\u3042\u308a\u3001rand()\u306f\u7591\u4f3c\u4e71\u6570\u3092\u751f\u6210\u3059\u308b<\/span><\/div>\n<div style=\"display:flex;align-items:flex-start;gap:8px;padding:6px 0;font-size:15px;line-height:1.6;\"><span style=\"color:#dc2626;font-size:16px;flex-shrink:0;margin-top:2px;\">&#10004;&#65039;<\/span><span><strong>srand(time(NULL))<\/strong>\u3092main\u95a2\u6570\u306e\u5148\u982d\u3067\u4e00\u5ea6\u3060\u3051\u547c\u3076\u3053\u3068\u3067\u6bce\u56de\u7570\u306a\u308b\u4e71\u6570\u5217\u306b\u306a\u308b<\/span><\/div>\n<div style=\"display:flex;align-items:flex-start;gap:8px;padding:6px 0;font-size:15px;line-height:1.6;\"><span style=\"color:#dc2626;font-size:16px;flex-shrink:0;margin-top:2px;\">&#10004;&#65039;<\/span><span><strong>n\u301cm\u306e\u4e71\u6570 = rand() % (m-n+1) + n<\/strong> \u3092\u899a\u3048\u308c\u3070\u4efb\u610f\u306e\u7bc4\u56f2\u306b\u5bfe\u5fdc\u3067\u304d\u308b<\/span><\/div>\n<div style=\"display:flex;align-items:flex-start;gap:8px;padding:6px 0;font-size:15px;line-height:1.6;\"><span style=\"color:#dc2626;font-size:16px;flex-shrink:0;margin-top:2px;\">&#10004;&#65039;<\/span><span>\u30eb\u30fc\u30d7\u5185\u3067\u306esrand()\u547c\u3073\u51fa\u3057\u30fb\u30ad\u30e3\u30b9\u30c8\u5fd8\u308c\u30fb\u30d8\u30c3\u30c0\u6f0f\u308c\u304c\u5178\u578b\u7684\u306a\u30d0\u30b0\u30d1\u30bf\u30fc\u30f3<\/span><\/div>\n<div style=\"display:flex;align-items:flex-start;gap:8px;padding:6px 0;font-size:15px;line-height:1.6;\"><span style=\"color:#dc2626;font-size:16px;flex-shrink:0;margin-top:2px;\">&#10004;&#65039;<\/span><span>\u7d71\u8a08\u30fb\u30b2\u30fc\u30e0\u958b\u767a\u306b\u306f<strong>\u30e1\u30eb\u30bb\u30f3\u30cc\u30c4\u30a4\u30b9\u30bf\u30fc<\/strong>\u3001\u30bb\u30ad\u30e5\u30ea\u30c6\u30a3\u306b\u306f<strong>OS\u306eAPI<\/strong>\u3092\u4f7f\u3046<\/span><\/div>\n<div style=\"display:flex;align-items:flex-start;gap:8px;padding:6px 0;font-size:15px;line-height:1.6;\"><span style=\"color:#dc2626;font-size:16px;flex-shrink:0;margin-top:2px;\">&#10004;&#65039;<\/span><span><strong>Claude Code<\/strong>\u306b\u65e5\u672c\u8a9e\u3067\u6307\u793a\u3059\u308b\u3060\u3051\u3067\u5b8c\u52d5\u3059\u308bC\u8a00\u8a9e\u30b3\u30fc\u30c9\u304c\u81ea\u52d5\u751f\u6210\u3067\u304d\u308b<\/span><\/div>\n\n<\/div>\n\n\n\n<div class=\"balloon-wrap\">\n  <div class=\"balloon-icon\">\n    <img decoding=\"async\" src=\"https:\/\/genai-ai.co.jp\/ai-kanri\/wp-content\/uploads\/2026\/04\/ceo-sugasawa.jpg\" alt=\"\u4ee3\u8868\u83c5\u6fa4\">\n    <span class=\"balloon-name\">\u4ee3\u8868\u83c5\u6fa4<\/span>\n  <\/div>\n  <div class=\"balloon-body\">C\u8a00\u8a9e\u306e\u4e71\u6570\u306f\u3001\u57fa\u672c\u30d1\u30bf\u30fc\u30f3\u3092\u4e00\u5ea6\u899a\u3048\u3066\u3057\u307e\u3048\u3070\u5f8c\u306f\u5fdc\u7528\u3059\u308b\u3060\u3051\u3067\u3059\u3002\u300c\u30b5\u30a4\u30b3\u30ed\u2192\u3058\u3083\u3093\u3051\u3093\u2192\u30b7\u30e3\u30c3\u30d5\u30eb\u300d\u3068\u6bb5\u968e\u7684\u306b\u30b5\u30f3\u30d7\u30eb\u3092\u81ea\u5206\u3067\u4f5c\u3063\u3066\u52d5\u304b\u3059\u3053\u3068\u3067\u3001\u78ba\u5b9f\u306b\u8eab\u306b\u3064\u304d\u307e\u3059\u3002\u8a70\u307e\u3063\u305f\u3068\u304d\u306fClaude Code\u306b\u6295\u3052\u3066\u3057\u307e\u3046\u306e\u304c\u6700\u3082\u52b9\u7387\u7684\u306a\u5b66\u7fd2\u6cd5\u306e\u4e00\u3064\u3067\u3059\u3002<\/div>\n<\/div>\n\n\n\n<h3 class=\"wp-block-heading\">\u30d7\u30ed\u30b0\u30e9\u30df\u30f3\u30b0\u306e\u5b66\u7fd2\u3082AI\u3092\u6d3b\u7528\u3057\u3066\u52b9\u7387\u5316\u3067\u304d\u307e\u3059<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">C\u8a00\u8a9e\u306e\u5b66\u7fd2\u306f\u3082\u3061\u308d\u3093\u3001\u696d\u52d9\u3067\u306e\u30d7\u30ed\u30b0\u30e9\u30e0\u958b\u767a\u3084\u81ea\u52d5\u5316\u30b9\u30af\u30ea\u30d7\u30c8\u4f5c\u6210\u307e\u3067\u3001Claude Code\u3092\u6d3b\u7528\u3059\u308b\u3053\u3068\u3067\u4f5c\u696d\u6642\u9593\u3092\u5927\u5e45\u306b\u77ed\u7e2e\u3067\u304d\u307e\u3059\u3002<br>AI\u9b3c\u7ba1\u7406\u3067\u306f\u3001Claude Code\u3092\u4f7f\u3063\u305f\u696d\u52d9\u81ea\u52d5\u5316\u306e\u8a2d\u8a08\u30fb\u5c0e\u5165\u652f\u63f4\u3092\u884c\u3063\u3066\u3044\u307e\u3059\u3002<\/p>\n\n\n\n<div class=\"balloon-wrap is-right\">\n  <div class=\"balloon-icon\">\n    <img decoding=\"async\" src=\"https:\/\/genai-ai.co.jp\/ai-kanri\/wp-content\/uploads\/2026\/04\/yamazaki-avatar.png\" alt=\"AI\u9b3c\u7ba1\u7406\u5c71\u5d0e\">\n    <span class=\"balloon-name\">AI\u9b3c\u7ba1\u7406\u5c71\u5d0e<\/span>\n  <\/div>\n  <div class=\"balloon-body\">\u300c\u30d7\u30ed\u30b0\u30e9\u30df\u30f3\u30b0\u304c\u3067\u304d\u306a\u304f\u3066\u3082AI\u3092\u4f7f\u3048\u3070\u696d\u52d9\u81ea\u52d5\u5316\u3067\u304d\u308b\u300d\u3068\u3044\u3046\u72b6\u6cc1\u304c\u5b9f\u969b\u306b\u6765\u3066\u3044\u307e\u3059\u3002\u307e\u305a\u306f\u7121\u6599\u76f8\u8ac7\u3067\u3001\u3042\u306a\u305f\u306e\u696d\u52d9\u3067AI\u304c\u6700\u3082\u8ca2\u732e\u3067\u304d\u308b\u9818\u57df\u3092\u4e00\u7dd2\u306b\u7279\u5b9a\u3057\u307e\u3057\u3087\u3046\u3002<\/div>\n<\/div>\n\n\n\n<div style=\"background:linear-gradient(135deg,#1a1a1a 0%,#2a1015 100%);border-radius:16px;padding:36px 32px;margin:48px 0 16px;color:#fff;\">\n  <p style=\"font-size:13px;font-weight:700;color:#dc2626;letter-spacing:2px;margin:0 0 12px;\">NEXT STEP<\/p>\n  <p style=\"font-size:22px;font-weight:800;line-height:1.5;margin:0 0 20px;\">\u3053\u306e\u8a18\u4e8b\u306e\u5185\u5bb9\u3092\u3001\u3042\u306a\u305f\u306e\u30d3\u30b8\u30cd\u30b9\u3067<br>\u5b9f\u8df5\u3057\u3066\u307f\u307e\u305b\u3093\u304b\uff1f<\/p>\n  <div style=\"background:rgba(255,255,255,0.06);border:1px solid rgba(255,255,255,0.12);border-radius:12px;padding:24px;max-width:560px;margin:0 auto;\">\n    <p style=\"font-size:13px;color:#dc2626;font-weight:700;margin:0 0 8px;\">AI\u6d3b\u7528\u3092\u81ea\u793e\u3067\u56de\u305b\u308b\u3088\u3046\u306b\u306a\u308a\u305f\u3044\u65b9\u3078<\/p>\n    <p style=\"font-size:20px;font-weight:800;margin:0 0 12px;\">AI\u9b3c\u7ba1\u7406<\/p>\n    <p style=\"font-size:14px;color:rgba(255,255,255,0.75);margin:0 0 20px;line-height:1.7;\">Claude Code\u30fbCowork\u5c0e\u5165\u652f\u63f4\u304b\u3089\u696d\u52d9\u8a2d\u8a08\u30fb\u793e\u5185\u6d78\u900f\u307e\u3067\u5b9f\u8df5\u30d9\u30fc\u30b9\u3067\u4f34\u8d70\u3002\u300c\u81ea\u793e\u3067\u56de\u305b\u308b\u7d44\u7e54\u300d\u309290\u65e5\u3067\u4f5c\u308b\u7d4c\u55b6\u8005\u5411\u3051\u30c8\u30ec\u30fc\u30cb\u30f3\u30b0\u3002<\/p>\n    <div style=\"text-align:center;\">\n      <a href=\"https:\/\/aikanri.genai-ai.co.jp\/?utm_source=blog&utm_medium=article&utm_campaign=cc-c-rand-random&utm_content=next-step-cta\" target=\"_blank\" rel=\"noopener\" style=\"display:inline-block;background:#dc2626;color:#fff;font-weight:700;font-size:15px;padding:14px 32px;border-radius:30px;text-decoration:none;\">AI\u9b3c\u7ba1\u7406\u3092\u8a73\u3057\u304f\u898b\u308b \u2192<\/a>\n    <\/div>\n  <\/div>\n<\/div>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"faq\">\u3088\u304f\u3042\u308b\u8cea\u554f<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">Q. rand()\u3092\u4f7f\u3046\u305f\u3081\u306b\u5fc5\u8981\u306a\u30d8\u30c3\u30c0\u30d5\u30a1\u30a4\u30eb\u306f\u4f55\u3067\u3059\u304b\uff1f<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">A. rand()\u3068srand()\u3092\u4f7f\u3046\u306b\u306f #include <stdlib.h> \u304c\u5fc5\u8981\u3067\u3059\u3002time()\u3067\u30b7\u30fc\u30c9\u3092\u8a2d\u5b9a\u3059\u308b\u5834\u5408\u306f\u3055\u3089\u306b #include <time.h> \u3082\u5fc5\u8981\u3067\u3059\u3002\u3069\u3061\u3089\u304b\u4e00\u65b9\u306e\u30a4\u30f3\u30af\u30eb\u30fc\u30c9\u5fd8\u308c\u304c\u539f\u56e0\u3067\u30b3\u30f3\u30d1\u30a4\u30eb\u8b66\u544a\u3084\u5b9f\u884c\u6642\u306e\u304a\u304b\u3057\u306a\u52d5\u4f5c\u304c\u8d77\u304d\u308b\u30b1\u30fc\u30b9\u304c\u591a\u3044\u305f\u3081\u3001\u4e71\u6570\u30b3\u30fc\u30c9\u3092\u66f8\u304f\u3068\u304d\u306f\u5fc5\u305a2\u884c\u3068\u3082\u30a4\u30f3\u30af\u30eb\u30fc\u30c9\u3057\u3066\u3044\u308b\u3053\u3068\u3092\u78ba\u8a8d\u3057\u3066\u304f\u3060\u3055\u3044\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Q. srand()\u3092for\u30eb\u30fc\u30d7\u306e\u4e2d\u306b\u5165\u308c\u305f\u3089\u6bce\u56de\u540c\u3058\u6570\u304c\u51fa\u308b\u306e\u306f\u306a\u305c\u3067\u3059\u304b\uff1f<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">A. \u30eb\u30fc\u30d7\u304c1\u79d2\u4ee5\u5185\u306b\u5b8c\u4e86\u3059\u308b\u5834\u5408\u3001time(NULL)\u306e\u8fd4\u308a\u5024\uff08\u79d2\u5358\u4f4d\u306eUnix\u30bf\u30a4\u30e0\uff09\u304c\u30eb\u30fc\u30d7\u5168\u4f53\u3067\u540c\u3058\u5024\u306b\u306a\u308b\u305f\u3081\u3067\u3059\u3002srand()\u306b\u540c\u3058\u5024\u304c\u6e21\u3055\u308c\u308b\u3068\u540c\u3058\u30b7\u30fc\u30c9\u304c\u8a2d\u5b9a\u3055\u308c\u308b\u305f\u3081\u3001rand()\u304c\u8fd4\u3059\u5024\u3082\u540c\u3058\u306b\u306a\u308a\u307e\u3059\u3002\u89e3\u6c7a\u7b56\u306fsrand()\u3092for\u30eb\u30fc\u30d7\u306e\u5916\u30fbmain\u95a2\u6570\u306e\u5148\u982d\u3067\u4e00\u5ea6\u3060\u3051\u547c\u3076\u3053\u3068\u3067\u3059\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Q. 1\u301c100\u306e\u4e71\u6570\u3092\u751f\u6210\u3059\u308b\u5f0f\u306f\u3069\u3046\u66f8\u304d\u307e\u3059\u304b\uff1f<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">A. rand() % 100 + 1 \u3068\u66f8\u304d\u307e\u3059\u3002rand() % 100 \u306f0\u301c99\u306e\u5024\u3092\u8fd4\u3059\u305f\u3081\u3001+1\u3059\u308b\u3053\u3068\u30671\u301c100\u306b\u306a\u308a\u307e\u3059\u3002\u4e00\u822c\u5f0f\u306f\u300cn\u301cm \u306e\u4e71\u6570 = rand() % (m - n + 1) + n\u300d\u3067\u3059\u30021\u301c100\u306e\u5834\u5408\u306f n=1\u3001m=100 \u306a\u306e\u3067 rand() % (100 - 1 + 1) + 1 = rand() % 100 + 1 \u3068\u306a\u308a\u307e\u3059\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Q. RAND_MAX\u306e\u5024\u306f\u3044\u304f\u3064\u3067\u3059\u304b\uff1f\u74b0\u5883\u306b\u3088\u3063\u3066\u5909\u308f\u308a\u307e\u3059\u304b\uff1f<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">A. RAND_MAX\u306fC\u8a00\u8a9e\u306e\u898f\u683c\u3067\u300c\u5c11\u306a\u304f\u3068\u308232767\uff082^15-1\uff09\u4ee5\u4e0a\u300d\u3068\u5b9a\u3081\u3089\u308c\u3066\u3044\u307e\u3059\u304c\u3001\u5b9f\u969b\u306e\u5024\u306f\u74b0\u5883\u306b\u3088\u3063\u3066\u7570\u306a\u308a\u307e\u3059\u3002Linux\uff08gcc\uff09\u3084macOS\uff08clang\uff09\u3067\u306f2,147,483,647\uff082^31-1\uff09\u3001Windows\uff08MSVC\uff09\u3067\u306f32767\u304c\u4e00\u822c\u7684\u3067\u3059\u3002\u81ea\u5206\u306e\u74b0\u5883\u306eRAND_MAX\u3092\u78ba\u8a8d\u3059\u308b\u306b\u306f printf(\"RAND_MAX=%d\\n\", RAND_MAX); \u3068\u66f8\u3044\u3066\u5b9f\u884c\u3057\u3066\u307f\u3066\u304f\u3060\u3055\u3044\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Q. rand()\u306f0.0\u301c1.0\u306e\u5c0f\u6570\u3092\u751f\u6210\u3067\u304d\u307e\u3059\u304b\uff1f<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">A. rand()\u81ea\u4f53\u306f\u6574\u6570\u5024\u3057\u304b\u8fd4\u3057\u307e\u305b\u3093\u304c\u3001(double)rand() \/ RAND_MAX \u3068\u3044\u3046\u5f0f\u30670.0\u301c1.0\u306e\u6d6e\u52d5\u5c0f\u6570\u70b9\u6570\u3092\u5f97\u3089\u308c\u307e\u3059\u3002\u30ad\u30e3\u30b9\u30c8(double)\u304c\u5fc5\u8981\u306a\u7406\u7531\u306f\u3001rand()\/RAND_MAX\u3092\u30ad\u30e3\u30b9\u30c8\u306a\u3057\u3067\u66f8\u304f\u3068\u6574\u6570\u9664\u7b97\u306b\u306a\u308a\u3001\u5e38\u306b0.0\u304c\u8fd4\u308b\u305f\u3081\u3067\u3059\u3002\u78ba\u7387\u8a08\u7b97\uff0850%\u306e\u78ba\u7387\u3067\u4f55\u304b\u3092\u3059\u308b\uff09\u306a\u3069\u306b\u4f7f\u3048\u307e\u3059\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Q. C\u8a00\u8a9e\u306erand()\u306f\u30b2\u30fc\u30e0\u958b\u767a\u306b\u4f7f\u3048\u307e\u3059\u304b\uff1f\u30e1\u30eb\u30bb\u30f3\u30cc\u30c4\u30a4\u30b9\u30bf\u30fc\u3068\u6bd4\u3079\u308b\u3068\uff1f<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">A. \u7c21\u5358\u306a\u30b2\u30fc\u30e0\u3084\u5b66\u7fd2\u7528\u9014\u306a\u3089rand()\u3067\u5341\u5206\u3067\u3059\u3002\u305f\u3060\u3057\u3001\u672c\u683c\u7684\u306a\u30b2\u30fc\u30e0\u958b\u767a\uff08\u7279\u306b\u30e9\u30f3\u30c0\u30e0\u8981\u7d20\u304c\u91cd\u8981\u306aRPG\u3084\u30ed\u30fc\u30b0\u30e9\u30a4\u30af\uff09\u3067\u306f\u3001rand()\u306e\u54c1\u8cea\uff08\u5468\u671f\u30fb\u5206\u5e03\u306e\u5747\u4e00\u6027\uff09\u306b\u4e0d\u6e80\u304c\u51fa\u308b\u5834\u5408\u304c\u3042\u308a\u307e\u3059\u3002\u305d\u306e\u5834\u5408\u306f\u30e1\u30eb\u30bb\u30f3\u30cc\u30c4\u30a4\u30b9\u30bf\u30fc\uff08MT19937\uff09\u3092\u4f7f\u3046\u3068\u307b\u307c\u3059\u3079\u3066\u306e\u554f\u984c\u304c\u89e3\u6c7a\u3057\u307e\u3059\u3002C++\u3092\u4f7f\u3048\u308b\u306a\u3089 std::mt19937 \u304c\u6a19\u6e96\u30e9\u30a4\u30d6\u30e9\u30ea\u306b\u542b\u307e\u308c\u3066\u304a\u308a\u624b\u8efd\u306b\u4f7f\u3048\u307e\u3059\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Q. \u6697\u53f7\u7528\u9014\u3067rand()\u3092\u4f7f\u3063\u3066\u3082\u5b89\u5168\u3067\u3059\u304b\uff1f<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">A. \u5b89\u5168\u3067\u306f\u3042\u308a\u307e\u305b\u3093\u3002rand()\u306f\u7591\u4f3c\u4e71\u6570\u3067\u3042\u308a\u3001\u30b7\u30fc\u30c9\u3055\u3048\u308f\u304b\u308c\u3070\u6b21\u306e\u5024\u304c\u4e88\u6e2c\u53ef\u80fd\u3067\u3059\u3002\u30d1\u30b9\u30ef\u30fc\u30c9\u30fb\u6697\u53f7\u9375\u30fb\u30bb\u30ad\u30e5\u30ea\u30c6\u30a3\u30c8\u30fc\u30af\u30f3\u306e\u751f\u6210\u306b\u306frand()\u3092\u7d76\u5bfe\u306b\u4f7f\u3063\u3066\u306f\u3044\u3051\u307e\u305b\u3093\u3002Linux\u3067\u306f getrandom() \u30b7\u30b9\u30c6\u30e0\u30b3\u30fc\u30eb\u3084 \/dev\/urandom\u3001Windows\u3067\u306f BCryptGenRandom() \u306a\u3069\u3001OS\u304c\u63d0\u4f9b\u3059\u308b\u30bb\u30ad\u30e5\u30ea\u30c6\u30a3\u7528\u4e71\u6570API\u3092\u4f7f\u3063\u3066\u304f\u3060\u3055\u3044\u3002<\/p>\n\n\n\n<script type=\"application\/ld+json\">\n{\n  \"@context\": \"https:\/\/schema.org\",\n  \"@type\": \"FAQPage\",\n  \"mainEntity\": [\n    {\n      \"@type\": \"Question\",\n      \"name\": \"rand()\u3092\u4f7f\u3046\u305f\u3081\u306b\u5fc5\u8981\u306a\u30d8\u30c3\u30c0\u30d5\u30a1\u30a4\u30eb\u306f\u4f55\u3067\u3059\u304b\uff1f\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"rand()\u3068srand()\u3092\u4f7f\u3046\u306b\u306f #include <stdlib.h> \u304c\u5fc5\u8981\u3067\u3059\u3002time()\u3067\u30b7\u30fc\u30c9\u3092\u8a2d\u5b9a\u3059\u308b\u5834\u5408\u306f\u3055\u3089\u306b #include <time.h> \u3082\u5fc5\u8981\u3067\u3059\u3002\u3069\u3061\u3089\u304b\u4e00\u65b9\u306e\u30a4\u30f3\u30af\u30eb\u30fc\u30c9\u5fd8\u308c\u304c\u539f\u56e0\u3067\u30b3\u30f3\u30d1\u30a4\u30eb\u8b66\u544a\u3084\u5b9f\u884c\u6642\u306e\u304a\u304b\u3057\u306a\u52d5\u4f5c\u304c\u8d77\u304d\u308b\u30b1\u30fc\u30b9\u304c\u591a\u3044\u305f\u3081\u3001\u4e71\u6570\u30b3\u30fc\u30c9\u3092\u66f8\u304f\u3068\u304d\u306f\u5fc5\u305a2\u884c\u3068\u3082\u30a4\u30f3\u30af\u30eb\u30fc\u30c9\u3057\u3066\u3044\u308b\u3053\u3068\u3092\u78ba\u8a8d\u3057\u3066\u304f\u3060\u3055\u3044\u3002\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"srand()\u3092for\u30eb\u30fc\u30d7\u306e\u4e2d\u306b\u5165\u308c\u305f\u3089\u6bce\u56de\u540c\u3058\u6570\u304c\u51fa\u308b\u306e\u306f\u306a\u305c\u3067\u3059\u304b\uff1f\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"\u30eb\u30fc\u30d7\u304c1\u79d2\u4ee5\u5185\u306b\u5b8c\u4e86\u3059\u308b\u5834\u5408\u3001time(NULL)\u306e\u8fd4\u308a\u5024\uff08\u79d2\u5358\u4f4d\u306eUnix\u30bf\u30a4\u30e0\uff09\u304c\u30eb\u30fc\u30d7\u5168\u4f53\u3067\u540c\u3058\u5024\u306b\u306a\u308b\u305f\u3081\u3067\u3059\u3002srand()\u306b\u540c\u3058\u5024\u304c\u6e21\u3055\u308c\u308b\u3068\u540c\u3058\u30b7\u30fc\u30c9\u304c\u8a2d\u5b9a\u3055\u308c\u308b\u305f\u3081\u3001rand()\u304c\u8fd4\u3059\u5024\u3082\u540c\u3058\u306b\u306a\u308a\u307e\u3059\u3002\u89e3\u6c7a\u7b56\u306fsrand()\u3092for\u30eb\u30fc\u30d7\u306e\u5916\u30fbmain\u95a2\u6570\u306e\u5148\u982d\u3067\u4e00\u5ea6\u3060\u3051\u547c\u3076\u3053\u3068\u3067\u3059\u3002\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"1\u301c100\u306e\u4e71\u6570\u3092\u751f\u6210\u3059\u308b\u5f0f\u306f\u3069\u3046\u66f8\u304d\u307e\u3059\u304b\uff1f\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"rand() % 100 + 1 \u3068\u66f8\u304d\u307e\u3059\u3002rand() % 100 \u306f0\u301c99\u306e\u5024\u3092\u8fd4\u3059\u305f\u3081\u3001+1\u3059\u308b\u3053\u3068\u30671\u301c100\u306b\u306a\u308a\u307e\u3059\u3002\u4e00\u822c\u5f0f\u306f\u300cn\u301cm \u306e\u4e71\u6570 = rand() % (m - n + 1) + n\u300d\u3067\u3059\u30021\u301c100\u306e\u5834\u5408\u306f n=1\u3001m=100 \u306a\u306e\u3067 rand() % (100 - 1 + 1) + 1 = rand() % 100 + 1 \u3068\u306a\u308a\u307e\u3059\u3002\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"RAND_MAX\u306e\u5024\u306f\u3044\u304f\u3064\u3067\u3059\u304b\uff1f\u74b0\u5883\u306b\u3088\u3063\u3066\u5909\u308f\u308a\u307e\u3059\u304b\uff1f\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"RAND_MAX\u306fC\u8a00\u8a9e\u306e\u898f\u683c\u3067\u300c\u5c11\u306a\u304f\u3068\u308232767\uff082^15-1\uff09\u4ee5\u4e0a\u300d\u3068\u5b9a\u3081\u3089\u308c\u3066\u3044\u307e\u3059\u304c\u3001\u5b9f\u969b\u306e\u5024\u306f\u74b0\u5883\u306b\u3088\u3063\u3066\u7570\u306a\u308a\u307e\u3059\u3002Linux\uff08gcc\uff09\u3084macOS\uff08clang\uff09\u3067\u306f2,147,483,647\uff082^31-1\uff09\u3001Windows\uff08MSVC\uff09\u3067\u306f32767\u304c\u4e00\u822c\u7684\u3067\u3059\u3002\u81ea\u5206\u306e\u74b0\u5883\u306eRAND_MAX\u3092\u78ba\u8a8d\u3059\u308b\u306b\u306f printf(\\\"RAND_MAX=%d\\\\n\\\", RAND_MAX); \u3068\u66f8\u3044\u3066\u5b9f\u884c\u3057\u3066\u307f\u3066\u304f\u3060\u3055\u3044\u3002\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"rand()\u306f0.0\u301c1.0\u306e\u5c0f\u6570\u3092\u751f\u6210\u3067\u304d\u307e\u3059\u304b\uff1f\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"rand()\u81ea\u4f53\u306f\u6574\u6570\u5024\u3057\u304b\u8fd4\u3057\u307e\u305b\u3093\u304c\u3001(double)rand() \/ RAND_MAX \u3068\u3044\u3046\u5f0f\u30670.0\u301c1.0\u306e\u6d6e\u52d5\u5c0f\u6570\u70b9\u6570\u3092\u5f97\u3089\u308c\u307e\u3059\u3002\u30ad\u30e3\u30b9\u30c8(double)\u304c\u5fc5\u8981\u306a\u7406\u7531\u306f\u3001rand()\/RAND_MAX\u3092\u30ad\u30e3\u30b9\u30c8\u306a\u3057\u3067\u66f8\u304f\u3068\u6574\u6570\u9664\u7b97\u306b\u306a\u308a\u3001\u5e38\u306b0.0\u304c\u8fd4\u308b\u305f\u3081\u3067\u3059\u3002\u78ba\u7387\u8a08\u7b97\uff0850%\u306e\u78ba\u7387\u3067\u4f55\u304b\u3092\u3059\u308b\uff09\u306a\u3069\u306b\u4f7f\u3048\u307e\u3059\u3002\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"C\u8a00\u8a9e\u306erand()\u306f\u30b2\u30fc\u30e0\u958b\u767a\u306b\u4f7f\u3048\u307e\u3059\u304b\uff1f\u30e1\u30eb\u30bb\u30f3\u30cc\u30c4\u30a4\u30b9\u30bf\u30fc\u3068\u6bd4\u3079\u308b\u3068\uff1f\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"\u7c21\u5358\u306a\u30b2\u30fc\u30e0\u3084\u5b66\u7fd2\u7528\u9014\u306a\u3089rand()\u3067\u5341\u5206\u3067\u3059\u3002\u305f\u3060\u3057\u3001\u672c\u683c\u7684\u306a\u30b2\u30fc\u30e0\u958b\u767a\uff08\u7279\u306b\u30e9\u30f3\u30c0\u30e0\u8981\u7d20\u304c\u91cd\u8981\u306aRPG\u3084\u30ed\u30fc\u30b0\u30e9\u30a4\u30af\uff09\u3067\u306f\u3001rand()\u306e\u54c1\u8cea\uff08\u5468\u671f\u30fb\u5206\u5e03\u306e\u5747\u4e00\u6027\uff09\u306b\u4e0d\u6e80\u304c\u51fa\u308b\u5834\u5408\u304c\u3042\u308a\u307e\u3059\u3002\u305d\u306e\u5834\u5408\u306f\u30e1\u30eb\u30bb\u30f3\u30cc\u30c4\u30a4\u30b9\u30bf\u30fc\uff08MT19937\uff09\u3092\u4f7f\u3046\u3068\u307b\u307c\u3059\u3079\u3066\u306e\u554f\u984c\u304c\u89e3\u6c7a\u3057\u307e\u3059\u3002C++\u3092\u4f7f\u3048\u308b\u306a\u3089 std::mt19937 \u304c\u6a19\u6e96\u30e9\u30a4\u30d6\u30e9\u30ea\u306b\u542b\u307e\u308c\u3066\u304a\u308a\u624b\u8efd\u306b\u4f7f\u3048\u307e\u3059\u3002\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"\u6697\u53f7\u7528\u9014\u3067rand()\u3092\u4f7f\u3063\u3066\u3082\u5b89\u5168\u3067\u3059\u304b\uff1f\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"\u5b89\u5168\u3067\u306f\u3042\u308a\u307e\u305b\u3093\u3002rand()\u306f\u7591\u4f3c\u4e71\u6570\u3067\u3042\u308a\u3001\u30b7\u30fc\u30c9\u3055\u3048\u308f\u304b\u308c\u3070\u6b21\u306e\u5024\u304c\u4e88\u6e2c\u53ef\u80fd\u3067\u3059\u3002\u30d1\u30b9\u30ef\u30fc\u30c9\u30fb\u6697\u53f7\u9375\u30fb\u30bb\u30ad\u30e5\u30ea\u30c6\u30a3\u30c8\u30fc\u30af\u30f3\u306e\u751f\u6210\u306b\u306frand()\u3092\u7d76\u5bfe\u306b\u4f7f\u3063\u3066\u306f\u3044\u3051\u307e\u305b\u3093\u3002Linux\u3067\u306f getrandom() \u30b7\u30b9\u30c6\u30e0\u30b3\u30fc\u30eb\u3084 \/dev\/urandom\u3001Windows\u3067\u306f BCryptGenRandom() \u306a\u3069\u3001OS\u304c\u63d0\u4f9b\u3059\u308b\u30bb\u30ad\u30e5\u30ea\u30c6\u30a3\u7528\u4e71\u6570API\u3092\u4f7f\u3063\u3066\u304f\u3060\u3055\u3044\u3002\"\n      }\n    }\n  ]\n}\n<\/script>\n\n\n","protected":false},"excerpt":{"rendered":"<p>C\u8a00\u8a9e\u306erand()\/srand()\u95a2\u6570\u3092\u5b8c\u5168\u89e3\u8aac\u3002RAND_MAX\u30fb\u7bc4\u56f2\u6307\u5b9a\u306e\u8a08\u7b97\u5f0f\u30fbtime()\u3067\u521d\u671f\u5316\u3059\u308b\u65b9\u6cd5\u304b\u3089\u3001\u30b5\u30a4\u30b3\u30ed\u30fb\u3058\u3083\u3093\u3051\u3093\u30fb\u4e71\u6570\u914d\u5217\u306e\u5b9f\u8df5\u30b3\u30fc\u30c9\u307e\u3067\u7db2\u7f85\u3002Claude Code\u3092\u4f7f\u3063\u305fC\u8a00\u8a9e\u30b3\u30fc\u30c9\u81ea\u52d5\u751f\u6210\u8853\u3082\u7d39\u4ecb\u3002<\/p>\n","protected":false},"author":1,"featured_media":18415,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"sitemap_hide":"","_veu_custom_css":"","vkexunit_cta_each_option":"","footnotes":"","rank_math_description":"C\u8a00\u8a9e\u306erand()\/srand()\u95a2\u6570\u3092\u5b8c\u5168\u89e3\u8aac\u3002RAND_MAX\u30fb\u7bc4\u56f2\u6307\u5b9a\u306e\u8a08\u7b97\u5f0f\u30fbtime()\u3067\u521d\u671f\u5316\u3059\u308b\u65b9\u6cd5\u304b\u3089\u3001\u30b5\u30a4\u30b3\u30ed\u30fb\u3058\u3083\u3093\u3051\u3093\u30fb\u4e71\u6570\u914d\u5217\u306e\u5b9f\u8df5\u30b3\u30fc\u30c9\u307e\u3067\u7db2\u7f85\u3002Claude Code\u3092\u4f7f\u3063\u305fC\u8a00\u8a9e\u30b3\u30fc\u30c9\u81ea\u52d5\u751f\u6210\u8853\u3082\u7d39\u4ecb\u3002","rank_math_focus_keyword":"C\u8a00\u8a9e \u4e71\u6570 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