{"id":18383,"date":"2026-07-19T03:22:22","date_gmt":"2026-07-18T18:22:22","guid":{"rendered":"https:\/\/genai-ai.co.jp\/ai-kanri\/?p=18383"},"modified":"2026-07-19T03:22:22","modified_gmt":"2026-07-18T18:22:22","slug":"cc-c-absolute-value","status":"publish","type":"post","link":"https:\/\/genai-ai.co.jp\/ai-kanri\/blog\/cc-c-absolute-value\/","title":{"rendered":"\u30102026\u5e747\u6708\u6700\u65b0\u3011C\u8a00\u8a9e\u3067\u7d76\u5bfe\u5024\u3092\u6c42\u3081\u308b\u65b9\u6cd5\u5b8c\u5168\u30ac\u30a4\u30c9\uff5cabs\u30fblabs\u30fbfabs\u30fbfabsf\u95a2\u6570\u306e\u4f7f\u3044\u5206\u3051\u3068\u5b9f\u8df5\u30b3\u30fc\u30c9\u4f8b"},"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-absolute-value.jpg\" alt=\"\u30102026\u5e747\u6708\u6700\u65b0\u3011C\u8a00\u8a9e\u3067\u7d76\u5bfe\u5024\u3092\u6c42\u3081\u308b\u65b9\u6cd5\u5b8c\u5168\u30ac\u30a4\u30c9\uff5cabs\u30fblabs\u30fbfabs\u30fbfabsf\u95a2\u6570\u306e\u4f7f\u3044\u5206\u3051\u3068\u5b9f\u8df5\u30b3\u30fc\u30c9\u4f8b\" 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>C\u8a00\u8a9e\u306b\u304a\u3051\u308b\u7d76\u5bfe\u5024\u3068\u306f<\/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>abs\u95a2\u6570\u306e\u4f7f\u3044\u65b9\uff08int\u578b\uff09<\/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>labs\u30fbllabs\u95a2\u6570\uff08long\/long long\u578b\uff09<\/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>fabs\u30fbfabsf\u95a2\u6570\uff08double\/float\u578b\uff09<\/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>\u30c7\u30fc\u30bf\u578b\u5225\u306e\u95a2\u6570\u9078\u629e\u30ac\u30a4\u30c9<\/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>if-else\u30fb\u4e09\u9805\u6f14\u7b97\u5b50\u3067\u81ea\u4f5c\u3059\u308b\u65b9\u6cd5<\/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>\u3088\u304f\u3042\u308b\u9593\u9055\u3044\u3068\u30a8\u30e9\u30fc<\/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\u7d76\u5bfe\u5024\u3092\u6c42\u3081\u305f\u3044\u3068\u304d\u3001\u3069\u306e\u95a2\u6570\u3092\u4f7f\u3048\u3070\u3088\u3044\u304b\u8ff7\u3063\u305f\u3053\u3068\u306f\u3042\u308a\u307e\u305b\u3093\u304b\uff1f\u300cabs\u95a2\u6570\u304c\u3042\u308b\u306e\u306f\u77e5\u3063\u3066\u3044\u308b\u304c\u3001float\u578b\u306b\u4f7f\u3063\u305f\u3089\u6b63\u3057\u304f\u52d5\u304b\u306a\u304b\u3063\u305f\u300d\u300cmath.h\u3092\u30a4\u30f3\u30af\u30eb\u30fc\u30c9\u3057\u3066\u3044\u306a\u3044\u306e\u306bfabs\u3092\u547c\u3093\u3067\u3082\u52d5\u304f\u6c17\u304c\u3059\u308b\u2026\u300d\u2014\u2014\u3053\u3046\u3057\u305f\u7591\u554f\u306f\u3001C\u8a00\u8a9e\u521d\u5b66\u8005\u3060\u3051\u3067\u306a\u304f\u3001\u4e2d\u7d1a\u8005\u306b\u3068\u3063\u3066\u3082\u610f\u5916\u306b\u591a\u3044\u843d\u3068\u3057\u7a74\u3067\u3059\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">C\u8a00\u8a9e\u306b\u306f\u7d76\u5bfe\u5024\u3092\u6c42\u3081\u308b\u95a2\u6570\u304c<strong>\u8907\u6570\u5b58\u5728<\/strong>\u3057\u307e\u3059\u3002\u305d\u308c\u305e\u308c\u304c\u3069\u306e\u30c7\u30fc\u30bf\u578b\u306b\u5bfe\u3057\u3066\u52d5\u4f5c\u3059\u308b\u304b\u3092\u7406\u89e3\u3057\u3066\u3044\u306a\u3044\u3068\u3001<strong>\u578b\u306e\u4e0d\u4e00\u81f4\u306b\u3088\u308b\u672a\u5b9a\u7fa9\u52d5\u4f5c\u3084\u7cbe\u5ea6\u306e\u6b20\u640d<\/strong>\u304c\u8d77\u304d\u307e\u3059\u3002\u300c\u52d5\u3044\u3066\u3044\u308b\u3088\u3046\u306b\u898b\u3048\u3066\u30d0\u30b0\u304c\u6f5c\u3093\u3067\u3044\u308b\u300d\u72b6\u614b\u304c\u6700\u3082\u5371\u967a\u3067\u3001\u7279\u306b\u7d44\u307f\u8fbc\u307f\u958b\u767a\u3084\u6570\u5024\u8a08\u7b97\u3067\u306f\u6df1\u523b\u306a\u554f\u984c\u306b\u767a\u5c55\u3059\u308b\u3053\u3068\u304c\u3042\u308a\u307e\u3059\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u3053\u306e\u8a18\u4e8b\u3067\u306f\u3001C\u8a00\u8a9e\u306e\u7d76\u5bfe\u5024\u95a2\u6570\u3092<strong>\u30c7\u30fc\u30bf\u578b\u3054\u3068\u306b\u4f53\u7cfb\u7684\u306b\u89e3\u8aac<\/strong>\u3057\u307e\u3059\u3002abs\u30fblabs\u30fbllabs\u30fbfabs\u30fbfabsf\u306e5\u95a2\u6570\u306e\u9055\u3044\u3092\u5b8c\u5168\u306b\u6574\u7406\u3057\u305f\u3046\u3048\u3067\u3001if-else\u6587\u3084\u30de\u30af\u30ed\u306b\u3088\u308b\u81ea\u4f5c\u5b9f\u88c5\u307e\u3067\u7db2\u7f85\u3057\u307e\u3059\u3002\u30b3\u30fc\u30c9\u4f8b\u306f\u3059\u3079\u3066\u30b3\u30f3\u30d1\u30a4\u30eb\u3067\u304d\u308b\u5b8c\u5168\u306a\u30b5\u30f3\u30d7\u30eb\u3067\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\">\u300cabs\u3092\u4f7f\u3048\u3070\u5927\u4e08\u592b\u300d\u3068\u601d\u3063\u3066\u3044\u305f\u65b9\u3082\u591a\u3044\u3068\u601d\u3044\u307e\u3059\u304c\u3001\u5b9f\u306fint\u578b\u306b\u3057\u304b\u6b63\u78ba\u306b\u52d5\u4f5c\u3057\u307e\u305b\u3093\u3002float\u578b\u3084long long\u578b\u306b\u306f\u5225\u306e\u95a2\u6570\u304c\u5fc5\u8981\u3067\u3059\u3002\u3053\u306e\u8a18\u4e8b\u3092\u8aad\u3081\u3070\u3001\u578b\u3092\u898b\u305f\u77ac\u9593\u306b\u6b63\u3057\u3044\u95a2\u6570\u304c\u9078\u3079\u308b\u3088\u3046\u306b\u306a\u308a\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>abs\u30fblabs\u30fbllabs\u30fbfabs\u30fbfabsf<\/strong>\u305d\u308c\u305e\u308c\u306e\u6b63\u78ba\u306a\u52d5\u4f5c\u3068\u30c7\u30fc\u30bf\u578b\u5bfe\u5fdc<\/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>stdlib.h\u3068math.h<\/strong>\u306e\u30a4\u30f3\u30af\u30eb\u30fc\u30c9\u304c\u5fc5\u8981\u306a\u5834\u9762\u306e\u9055\u3044<\/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>\u578b\u30df\u30b9\u30de\u30c3\u30c1<\/strong>\u306b\u3088\u308b\u30d0\u30b0\u304c\u767a\u751f\u3059\u308b\u30e1\u30ab\u30cb\u30ba\u30e0\u3068\u56de\u907f\u65b9\u6cd5<\/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>if-else\u30fb\u4e09\u9805\u6f14\u7b97\u5b50\u30fb\u30de\u30af\u30ed<\/strong>\u306b\u3088\u308b\u7d76\u5bfe\u5024\u306e\u81ea\u4f5c\u5b9f\u88c5\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><strong>\u3088\u304f\u3042\u308b\u30b3\u30f3\u30d1\u30a4\u30eb\u30a8\u30e9\u30fc\u3068\u8b66\u544a<\/strong>\u306e\u539f\u56e0\u3068\u4fee\u6b63\u65b9\u6cd5<\/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>\u30c7\u30fc\u30bf\u578b\u5225\u306e\u6b63\u3057\u3044\u95a2\u6570\u9078\u629e<\/strong>\u30d5\u30ed\u30fc\u30c1\u30e3\u30fc\u30c8<\/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\">\u300c\u3069\u306e\u95a2\u6570\u3092\u4f7f\u3048\u3070\u6b63\u89e3\u304b\u300d\u3092\u6bce\u56de\u8abf\u3079\u306a\u304f\u3066\u6e08\u3080\u3088\u3046\u306b\u3001\u3053\u306e\u8a18\u4e8b\u3067\u306f\u5224\u65ad\u30d5\u30ed\u30fc\u3092\u56f3\u89e3\u3057\u3066\u3044\u307e\u3059\u3002\u4e00\u5ea6\u8aad\u3081\u3070\u8ff7\u3044\u304c\u306a\u304f\u306a\u308a\u307e\u3059\u3002<\/div>\n<\/div>\n\n\n\n<div style=\"margin:48px 0 8px;text-align:center;\">\n  <a href=\"https:\/\/aikanri.genai-ai.co.jp\/?utm_source=blog&utm_medium=article&utm_campaign=cc-c-absolute-value&utm_content=h2-banner\" target=\"_blank\" rel=\"noopener\">\n    <img decoding=\"async\" src=\"https:\/\/genai-ai.co.jp\/ai-kanri\/wp-content\/uploads\/2026\/04\/cta_blog.jpg\" alt=\"Claude Code\u3092\u7d4c\u55b6\u306b\u6d3b\u304b\u3057\u305f\u3044\u65b9\u3078 \u2014 AI\u9b3c\u7ba1\u7406\" style=\"width:100%;max-width:800px;height:auto;border-radius:8px;display:inline-block;\">\n  <\/a>\n<\/div>\n\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;\">C\u8a00\u8a9e\u306b\u304a\u3051\u308b\u7d76\u5bfe\u5024\u3068\u306f<\/span>\n  <span class=\"section-desc\">\u6570\u5b66\u7684\u5b9a\u7fa9\u304b\u3089\u30d7\u30ed\u30b0\u30e9\u30df\u30f3\u30b0\u3078\u306e\u5bfe\u5fdc\u307e\u3067<\/span>\n<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u7d76\u5bfe\u5024\uff08Absolute Value\uff09\u3068\u306f\u3001\u6570\u5024\u306e\u300c\u7b26\u53f7\u3092\u53d6\u308a\u9664\u3044\u305f\u5927\u304d\u3055\u300d\u3092\u6307\u3057\u307e\u3059\u3002\u6570\u5b66\u3067\u306f |x| \u3068\u3044\u3046\u8a18\u6cd5\u3067\u8868\u3057\u3001x \u304c\u6b63\u306e\u5834\u5408\u306f\u305d\u306e\u307e\u307e x\u3001\u8ca0\u306e\u5834\u5408\u306f -x\u30010 \u306e\u5834\u5408\u306f 0 \u3092\u8fd4\u3057\u307e\u3059\u3002\u3053\u306e\u6982\u5ff5\u306fC\u8a00\u8a9e\u3067\u3082\u540c\u69d8\u3067\u3059\u304c\u3001\u30d7\u30ed\u30b0\u30e9\u30df\u30f3\u30b0\u306b\u304a\u3044\u3066\u306f<strong>\u30c7\u30fc\u30bf\u578b\u306b\u5fdc\u3058\u305f\u5c02\u7528\u306e\u95a2\u6570\u3092\u4f7f\u3044\u5206\u3051\u308b\u5fc5\u8981<\/strong>\u304c\u3042\u308a\u307e\u3059\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u305f\u3068\u3048\u3070\u3001\u6570\u5b66\u3067\u306f |\u22125.5| = 5.5 \u306f\u81ea\u660e\u3067\u3059\u304c\u3001C\u8a00\u8a9e\u306e abs(-5.5) \u306f\u6574\u6570\u90e8\u3057\u304b\u51e6\u7406\u3067\u304d\u306a\u3044\u305f\u3081\u3001\u5185\u90e8\u3067 float \u304c int \u306b\u5909\u63db\u3055\u308c 5 \u306b\u306a\u3063\u3066\u3057\u307e\u3044\u307e\u3059\u3002\u3053\u308c\u306f\u300c\u30b3\u30f3\u30d1\u30a4\u30eb\u30a8\u30e9\u30fc\u306b\u306f\u306a\u3089\u306a\u3044\u304c\u3001\u610f\u56f3\u3057\u305f\u7d50\u679c\u306b\u306a\u3089\u306a\u3044\u300d\u5178\u578b\u7684\u306a\u7f60\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>\u7d76\u5bfe\u5024\uff08Absolute Value\uff09<\/strong>\uff1a\u6570\u76f4\u7dda\u4e0a\u3067\u306e\u539f\u70b9\uff080\uff09\u304b\u3089\u306e\u8ddd\u96e2\u3092\u8868\u3059\u5024\u3002\u6b63\u306e\u6570\u306f\u305d\u306e\u307e\u307e\u3001\u8ca0\u306e\u6570\u306f\u7b26\u53f7\u3092\u53cd\u8ee2\u3055\u305b\u305f\u5024\u3068\u306a\u308b\u3002\u6570\u5b66\u8a18\u6cd5\u3067\u306f |x| \u3067\u8868\u3055\u308c\u3001\u5e38\u306b0\u4ee5\u4e0a\u306e\u5024\u3092\u8fd4\u3059\u3002C\u8a00\u8a9e\u3067\u306f\u578b\u306b\u5fdc\u3058\u305f\u5c02\u7528\u95a2\u6570\uff08abs\/labs\/fabs\u7b49\uff09\u3092\u4f7f\u3063\u3066\u6c42\u3081\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>\u30d8\u30c3\u30c0\u30d5\u30a1\u30a4\u30eb\uff08Header File\uff09<\/strong>\uff1aC\u8a00\u8a9e\u3067\u6a19\u6e96\u30e9\u30a4\u30d6\u30e9\u30ea\u306e\u95a2\u6570\u3092\u4f7f\u7528\u3059\u308b\u305f\u3081\u306b\u5148\u982d\u3067\u8aad\u307f\u8fbc\u3080\u5ba3\u8a00\u30d5\u30a1\u30a4\u30eb\u3002\u62e1\u5f35\u5b50\u306f .h\u3002#include <stdlib.h> \u306e\u3088\u3046\u306b\u8a18\u8ff0\u3059\u308b\u3002\u30d8\u30c3\u30c0\u30d5\u30a1\u30a4\u30eb\u306b\u306f\u95a2\u6570\u306e\u30d7\u30ed\u30c8\u30bf\u30a4\u30d7\u5ba3\u8a00\u304c\u542b\u307e\u308c\u3066\u304a\u308a\u3001\u3053\u308c\u3092\u7701\u7565\u3059\u308b\u3068\u30b3\u30f3\u30d1\u30a4\u30e9\u304c\u95a2\u6570\u306e\u578b\u60c5\u5831\u3092\u77e5\u3089\u306a\u3044\u307e\u307e\u547c\u3073\u51fa\u3059\u3053\u3068\u306b\u306a\u308a\u3001\u672a\u5b9a\u7fa9\u52d5\u4f5c\u306e\u539f\u56e0\u3068\u306a\u308b\u3002<\/p>\n<\/div>\n\n\n\n<p class=\"wp-block-paragraph\">C\u8a00\u8a9e\u306e\u7d76\u5bfe\u5024\u95a2\u6570\u306f\u3001\u4f7f\u7528\u3059\u308b\u30d8\u30c3\u30c0\u30d5\u30a1\u30a4\u30eb\u3068\u30c7\u30fc\u30bf\u578b\u306e\u5bfe\u5fdc\u95a2\u4fc2\u3092\u6b63\u78ba\u306b\u628a\u63e1\u3059\u308b\u3053\u3068\u304c\u91cd\u8981\u3067\u3059\u3002\u4ee5\u4e0b\u306e\u30d5\u30ed\u30fc\u56f3\u3067\u307e\u305a\u306f\u5168\u4f53\u50cf\u3092\u63b4\u307f\u307e\u3057\u3087\u3046\u3002<\/p>\n\n\n\n<div class=\"g-flow-row\" style=\"margin:24px 0;\">\n  <div class=\"g-flow-item\">\u6570\u5024\u306e\u578b\u3092\u78ba\u8a8d<\/div>\n  <div class=\"g-flow-arrow\">&#8594;<\/div>\n  <div class=\"g-flow-item\">int\u578b \u2192 abs()<\/div>\n  <div class=\"g-flow-arrow\">&#8594;<\/div>\n  <div class=\"g-flow-item\">long\u578b \u2192 labs()<\/div>\n  <div class=\"g-flow-arrow\">&#8594;<\/div>\n  <div class=\"g-flow-item\">float\/double\u578b \u2192 fabs()\/fabsf()<\/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\u578b\u3092\u78ba\u8a8d\u3057\u3066\u304b\u3089\u95a2\u6570\u3092\u9078\u3076\u300d\u3068\u3044\u3046\u7fd2\u6163\u3092\u3064\u3051\u308b\u3060\u3051\u3067\u3001\u7d76\u5bfe\u5024\u95a2\u9023\u306e\u30d0\u30b0\u306f\u307b\u307c\u30bc\u30ed\u306b\u3067\u304d\u307e\u3059\u3002\u6700\u521d\u306f\u9762\u5012\u3067\u3082\u3001\u6163\u308c\u308b\u3068\u4e00\u77ac\u3067\u308f\u304b\u308b\u3088\u3046\u306b\u306a\u308a\u307e\u3059\u3002<\/div>\n<\/div>\n\n\n\n<p class=\"wp-block-paragraph\">\u307e\u305f\u3001C\u8a00\u8a9e\u3067\u306f<strong>\u30d8\u30c3\u30c0\u30d5\u30a1\u30a4\u30eb\u306e\u30a4\u30f3\u30af\u30eb\u30fc\u30c9\u5fd8\u308c<\/strong>\u304c\u3088\u304f\u3042\u308b\u554f\u984c\u3067\u3059\u3002\u6574\u6570\u5411\u3051\u306eabs\/labs\/llabas\u306f <code>&lt;stdlib.h&gt;<\/code> \u3092\u30a4\u30f3\u30af\u30eb\u30fc\u30c9\u3057\u3066\u4f7f\u3044\u307e\u3059\u3002\u6d6e\u52d5\u5c0f\u6570\u70b9\u5411\u3051\u306efabs\/fabsf\u306f <code>&lt;math.h&gt;<\/code> \u304c\u5fc5\u8981\u3067\u3059\u3002\u3053\u306e\u4f7f\u3044\u5206\u3051\u304c\u30df\u30b9\u306e\u539f\u56e0\u306b\u306a\u308a\u3084\u3059\u3044\u305f\u3081\u3001\u672c\u8a18\u4e8b\u3067\u3057\u3063\u304b\u308a\u89e3\u8aac\u3057\u307e\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;\">C99\u4ee5\u964d\u306eabs\u95a2\u6570\u306e\u52d5\u4f5c<\/strong>\n  <\/div>\n  <p style=\"margin:0;font-size:15px;line-height:1.8;color:#333;\">C99\u898f\u683c\u304b\u3089\u306f <code>&lt;stdlib.h&gt;<\/code> \u306eabs\u95a2\u6570\u304clong int\u5f15\u6570\u306b\u5bfe\u3057\u3066labs\u76f8\u5f53\u306e\u52d5\u4f5c\u3092\u3059\u308b\u51e6\u7406\u7cfb\u3082\u3042\u308a\u307e\u3059\u304c\u3001\u79fb\u690d\u6027\u306e\u3042\u308b\u30b3\u30fc\u30c9\u3092\u66f8\u304f\u305f\u3081\u306b\u306f\u5e38\u306b\u578b\u306b\u5408\u3063\u305f\u5c02\u7528\u95a2\u6570\u3092\u660e\u793a\u7684\u306b\u4f7f\u3046\u3053\u3068\u3092\u63a8\u5968\u3057\u307e\u3059\u3002\u30b3\u30f3\u30d1\u30a4\u30e9\u3084\u74b0\u5883\u4f9d\u5b58\u306b\u983c\u308b\u306e\u306f\u907f\u3051\u307e\u3057\u3087\u3046\u3002<\/p>\n<\/div>\n\n\n\n<p class=\"wp-block-paragraph\">\u7d76\u5bfe\u5024\u306e\u8a08\u7b97\u304c\u5fc5\u8981\u306a\u30e6\u30fc\u30b9\u30b1\u30fc\u30b9\u306f\u975e\u5e38\u306b\u591a\u304f\u3042\u308a\u307e\u3059\u3002\u305f\u3068\u3048\u3070\u30012\u70b9\u9593\u306e\u8ddd\u96e2\u8a08\u7b97\u3001\u8aa4\u5dee\u306e\u8a55\u4fa1\u3001\u30c7\u30fc\u30bf\u306e\u6b63\u898f\u5316\u3001\u30b0\u30e9\u30d5\u30a3\u30c3\u30af\u30b9\u3067\u306e\u5ea7\u6a19\u8a08\u7b97\u3001\u97f3\u58f0\u4fe1\u53f7\u51e6\u7406\u306a\u3069\u3001\u79d1\u5b66\u6280\u8853\u8a08\u7b97\u304b\u3089\u7d44\u307f\u8fbc\u307f\u7cfb\u307e\u3067\u5e45\u5e83\u3044\u5834\u9762\u3067\u767b\u5834\u3057\u307e\u3059\u3002\u305d\u306e\u305f\u3081\u3001\u6b63\u78ba\u306a\u95a2\u6570\u9078\u629e\u306f\u5b9f\u52d9\u4e0a\u306e\u91cd\u8981\u30b9\u30ad\u30eb\u3067\u3059\u3002<\/p>\n\n\n\n<div style=\"margin:48px 0 8px;text-align:center;\">\n  <a href=\"https:\/\/aikanri.genai-ai.co.jp\/?utm_source=blog&utm_medium=article&utm_campaign=cc-c-absolute-value&utm_content=h2-banner\" target=\"_blank\" rel=\"noopener\">\n    <img decoding=\"async\" src=\"https:\/\/genai-ai.co.jp\/ai-kanri\/wp-content\/uploads\/2026\/04\/cta_blog.jpg\" alt=\"Claude Code\u3092\u7d4c\u55b6\u306b\u6d3b\u304b\u3057\u305f\u3044\u65b9\u3078 \u2014 AI\u9b3c\u7ba1\u7406\" style=\"width:100%;max-width:800px;height:auto;border-radius:8px;display:inline-block;\">\n  <\/a>\n<\/div>\n\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;\">INT TYPE<\/span>\n  <span class=\"section-title\" style=\"display:block;\">abs\u95a2\u6570\u306e\u4f7f\u3044\u65b9\uff08int\u578b\uff09<\/span>\n  <span class=\"section-desc\">stdlib.h\u3092\u30a4\u30f3\u30af\u30eb\u30fc\u30c9\u3057\u3066int\u578b\u306e\u7d76\u5bfe\u5024\u3092\u53d6\u5f97\u3059\u308b<\/span>\n<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">abs\u95a2\u6570\u306fC\u8a00\u8a9e\u3067\u6700\u3082\u3088\u304f\u4f7f\u308f\u308c\u308b\u7d76\u5bfe\u5024\u95a2\u6570\u3067\u3059\u3002<strong>int\u578b\uff08\u6574\u6570\u578b\uff09\u306e\u7d76\u5bfe\u5024\u3092\u6c42\u3081\u308b<\/strong>\u305f\u3081\u306b\u8a2d\u8a08\u3055\u308c\u3066\u304a\u308a\u3001<code>&lt;stdlib.h&gt;<\/code> \u3092\u30a4\u30f3\u30af\u30eb\u30fc\u30c9\u3059\u308b\u3053\u3068\u3067\u4f7f\u3048\u307e\u3059\u3002\u95a2\u6570\u306e\u30b7\u30b0\u30cd\u30c1\u30e3\u306f <code>int abs(int x);<\/code> \u3067\u3059\u3002\u5f15\u6570\u3082\u623b\u308a\u5024\u3082 int \u578b\u3067\u3042\u308b\u3053\u3068\u306b\u6ce8\u610f\u3057\u3066\u304f\u3060\u3055\u3044\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>stdlib.h<\/strong>\uff1aStandard Library \u306e\u7565\u3002C\u8a00\u8a9e\u306e\u6a19\u6e96\u30e9\u30a4\u30d6\u30e9\u30ea\u30d8\u30c3\u30c0\u306e\u4e00\u3064\u3067\u3001\u30e1\u30e2\u30ea\u7ba1\u7406\uff08malloc\/free\uff09\u3001\u6587\u5b57\u5217\u5909\u63db\uff08atoi\/strtol\uff09\u3001\u4e71\u6570\uff08rand\uff09\u3001\u30d7\u30ed\u30bb\u30b9\u5236\u5fa1\uff08exit\uff09\u3001\u7d76\u5bfe\u5024\uff08abs\/labs\/llabs\uff09\u306a\u3069\u306e\u6c4e\u7528\u30e6\u30fc\u30c6\u30a3\u30ea\u30c6\u30a3\u95a2\u6570\u304c\u5ba3\u8a00\u3055\u308c\u3066\u3044\u308b\u3002\u307b\u307c\u3059\u3079\u3066\u306eC\u8a00\u8a9e\u30d7\u30ed\u30b0\u30e9\u30e0\u3067\u4f7f\u7528\u3055\u308c\u308b\u57fa\u672c\u30d8\u30c3\u30c0\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>int\u578b<\/strong>\uff1aC\u8a00\u8a9e\u306e\u57fa\u672c\u6574\u6570\u578b\u3002\u591a\u304f\u306e\u74b0\u5883\u3067\u306f32\u30d3\u30c3\u30c8\u7b26\u53f7\u4ed8\u304d\u6574\u6570\u3067\u3001\u683c\u7d0d\u3067\u304d\u308b\u7bc4\u56f2\u306f -2,147,483,648 \u301c 2,147,483,647\u3002abs()\u95a2\u6570\u306f\u3053\u306e\u7bc4\u56f2\u306e\u6574\u6570\u306e\u7d76\u5bfe\u5024\u3092\u6b63\u78ba\u306b\u6c42\u3081\u308b\u3002\u305f\u3060\u3057 INT_MIN\uff08-2147483648\uff09\u306e\u7d76\u5bfe\u5024\u306f\u540c\u578b\u3067\u8868\u73fe\u3067\u304d\u306a\u3044\u305f\u3081\u3001\u3053\u306e\u5024\u3092abs()\u306b\u6e21\u3059\u3068\u672a\u5b9a\u7fa9\u52d5\u4f5c\u306b\u306a\u308b\u70b9\u306b\u6ce8\u610f\u304c\u5fc5\u8981\u3002<\/p>\n<\/div>\n\n\n\n<p class=\"wp-block-paragraph\">\u4ee5\u4e0b\u306f abs \u95a2\u6570\u306e\u57fa\u672c\u7684\u306a\u4f7f\u3044\u65b9\u3092\u793a\u3059\u5b8c\u5168\u306a\u30b5\u30f3\u30d7\u30eb\u30d7\u30ed\u30b0\u30e9\u30e0\u3067\u3059\u3002<\/p>\n\n\n\n<pre style=\"background:#1e1e1e;color:#d4d4d4;padding:20px 24px;border-radius:8px;overflow-x:auto;line-height:1.7;margin:20px 0;font-size:14px;\"><code>#include &lt;stdio.h&gt;\n#include &lt;stdlib.h&gt;  \/* abs() \u3092\u4f7f\u3046\u305f\u3081\u306b\u5fc5\u8981 *\/\n\nint main(void) {\n    int a = -42;\n    int b = 100;\n    int c = 0;\n\n    printf(\"abs(%d) = %d\\n\", a, abs(a));   \/* abs(-42) = 42 *\/\n    printf(\"abs(%d) = %d\\n\", b, abs(b));   \/* abs(100) = 100 *\/\n    printf(\"abs(%d) = %d\\n\", c, abs(c));   \/* abs(0) = 0 *\/\n\n    \/* \u5dee\u5206\u306e\u7d76\u5bfe\u5024\u3092\u6c42\u3081\u308b\u4f8b\uff08\u8ddd\u96e2\u8a08\u7b97\uff09 *\/\n    int x1 = 5, x2 = -3;\n    int distance = abs(x1 - x2);\n    printf(\"x1=%d \u3068 x2=%d \u306e\u8ddd\u96e2: %d\\n\", x1, x2, distance); \/* 8 *\/\n\n    return 0;\n}<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">\u3053\u306e\u30d7\u30ed\u30b0\u30e9\u30e0\u3092\u30b3\u30f3\u30d1\u30a4\u30eb\u3057\u3066\u5b9f\u884c\u3059\u308b\u3068\u3001\u4ee5\u4e0b\u306e\u51fa\u529b\u304c\u5f97\u3089\u308c\u307e\u3059\u3002<\/p>\n\n\n\n<pre style=\"background:#1e1e1e;color:#d4d4d4;padding:20px 24px;border-radius:8px;overflow-x:auto;line-height:1.7;margin:20px 0;font-size:14px;\"><code>abs(-42) = 42\nabs(100) = 100\nabs(0) = 0\nx1=5 \u3068 x2=-3 \u306e\u8ddd\u96e2: 8<\/code><\/pre>\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\">abs\u95a2\u6570\u306f\u975e\u5e38\u306b\u30b7\u30f3\u30d7\u30eb\u3067\u3059\u304c\u3001\u300cstdlib.h\u306e\u30a4\u30f3\u30af\u30eb\u30fc\u30c9\u3092\u5fd8\u308c\u308b\u300d\u300cfloat\u578b\u306e\u5024\u3092\u6e21\u3057\u3066\u3057\u307e\u3046\u300d\u3068\u3044\u30462\u3064\u306e\u30df\u30b9\u304c\u983b\u767a\u3057\u307e\u3059\u3002\u30b3\u30fc\u30c9\u30ec\u30d3\u30e5\u30fc\u3067\u3082\u983b\u7e41\u306b\u6307\u6458\u3055\u308c\u308b\u30dd\u30a4\u30f3\u30c8\u3067\u3059\u3002<\/div>\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;\">int\u578b\u4ee5\u5916\u306babs()\u3092\u4f7f\u3046\u3068\u7cbe\u5ea6\u304c\u5931\u308f\u308c\u308b<\/strong>\n  <\/div>\n  <p style=\"margin:0;font-size:15px;line-height:1.8;color:#333;\">abs(-3.14) \u306e\u3088\u3046\u306bfloat\/double\u578b\u306e\u5024\u3092abs()\u306b\u6e21\u3059\u3068\u3001\u6697\u9ed9\u306e\u578b\u5909\u63db\u306b\u3088\u3063\u3066float\u306e\u5c0f\u6570\u90e8\u304c\u5207\u308a\u6368\u3066\u3089\u308c\u3066int\u306b\u306a\u3063\u3066\u304b\u3089\u51e6\u7406\u3055\u308c\u307e\u3059\u3002abs(-3.14)\u306f3\u3092\u8fd4\u3057\u3001\u5c0f\u6570\u70b9\u4ee5\u4e0b\u306e\u60c5\u5831\u304c\u5b8c\u5168\u306b\u5931\u308f\u308c\u307e\u3059\u3002\u30b3\u30f3\u30d1\u30a4\u30eb\u6642\u306b\u8b66\u544a\u304c\u51fa\u308b\u5834\u5408\u3082\u3042\u308a\u307e\u3059\u304c\u3001\u8b66\u544a\u306a\u3057\u3067\u901a\u308b\u30b1\u30fc\u30b9\u3082\u3042\u308b\u305f\u3081\u6ce8\u610f\u304c\u5fc5\u8981\u3067\u3059\u3002float\/double\u306b\u306ffabs()\/fabsf()\u3092\u4f7f\u3044\u307e\u3057\u3087\u3046\u3002<\/p>\n<\/div>\n\n\n\n<p class=\"wp-block-paragraph\">abs\u95a2\u6570\u3092\u5b9f\u969b\u306e\u8a08\u7b97\u306b\u4f7f\u3046\u5834\u9762\u3092\u3044\u304f\u3064\u304b\u78ba\u8a8d\u3057\u307e\u3057\u3087\u3046\u3002\u6570\u5024\u306e\u5dee\u306e\u7d76\u5bfe\u5024\u3092\u4f7f\u3063\u305f\u8aa4\u5dee\u30c1\u30a7\u30c3\u30af\u3001\u914d\u5217\u8981\u7d20\u306e\u6b63\u898f\u5316\u306a\u3069\u3001\u5b9f\u52d9\u3067\u983b\u7e41\u306b\u4f7f\u3046\u30d1\u30bf\u30fc\u30f3\u3067\u3059\u3002<\/p>\n\n\n\n<pre style=\"background:#1e1e1e;color:#d4d4d4;padding:20px 24px;border-radius:8px;overflow-x:auto;line-height:1.7;margin:20px 0;font-size:14px;\"><code>#include &lt;stdio.h&gt;\n#include &lt;stdlib.h&gt;\n\nint main(void) {\n    \/* \u8aa4\u5dee\u30c1\u30a7\u30c3\u30af: \u671f\u5f85\u5024\u3068\u5b9f\u6e2c\u5024\u306e\u5dee\u304c\u8a31\u5bb9\u7bc4\u56f2\u5185\u304b\u3069\u3046\u304b *\/\n    int expected = 100;\n    int actual   = 97;\n    int tolerance = 5;\n\n    if (abs(expected - actual) &lt;= tolerance) {\n        printf(\"\u8a31\u5bb9\u7bc4\u56f2\u5185: \u5dee=%d\\n\", abs(expected - actual));\n    } else {\n        printf(\"\u8a31\u5bb9\u7bc4\u56f2\u5916: \u5dee=%d\\n\", abs(expected - actual));\n    }\n\n    \/* \u914d\u5217\u306e\u5404\u8981\u7d20\u306e\u7d76\u5bfe\u5024\u3092\u6c42\u3081\u308b *\/\n    int arr[] = {-10, 3, -7, 0, 15, -2};\n    int n = sizeof(arr) \/ sizeof(arr[0]);\n\n    printf(\"\u7d76\u5bfe\u5024\u306e\u914d\u5217: \");\n    for (int i = 0; i &lt; n; i++) {\n        printf(\"%d \", abs(arr[i]));\n    }\n    printf(\"\\n\");\n\n    return 0;\n}<\/code><\/pre>\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;\">abs\u95a2\u6570\u306e\u623b\u308a\u5024\u306fint\u578b<\/strong>\n  <\/div>\n  <p style=\"margin:0;font-size:15px;line-height:1.8;color:#333;\">abs()\u306e\u623b\u308a\u5024\u306fint\u578b\u3067\u3059\u3002long\u578b\u3084long long\u578b\u306e\u5024\u3092\u6271\u3044\u305f\u3044\u5834\u5408\u306f\u623b\u308a\u5024\u306e\u578b\u3082\u4e00\u81f4\u3057\u3066\u3044\u306a\u3044\u3068\u3001\u5927\u304d\u306a\u6570\u5024\u3067\u6b63\u3057\u304f\u52d5\u4f5c\u3057\u307e\u305b\u3093\u3002int\u578b\u306e\u6700\u5927\u5024\uff082147483647\uff09\u3092\u8d85\u3048\u308b\u6570\u3092\u6271\u3046\u5834\u5408\u306f\u5f8c\u8ff0\u306elabs()\/llabs()\u3092\u4f7f\u3044\u307e\u3057\u3087\u3046\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\">abs\u306f\u30b7\u30f3\u30d7\u30eb\u306a\u5206\u3001\u4f7f\u7528\u983b\u5ea6\u304c\u9ad8\u3044\u304b\u3089\u3053\u305d\u6cb9\u65ad\u3057\u304c\u3061\u3067\u3059\u3002\u300cint\u578b\u5c02\u7528\u300d\u3068\u5f37\u304f\u610f\u8b58\u3059\u308b\u3060\u3051\u3067\u591a\u304f\u306e\u30d0\u30b0\u3092\u9632\u3052\u307e\u3059\u3002\u578b\u306e\u30b5\u30a4\u30ba\u306b\u5fdc\u3058\u305f\u95a2\u6570\u9078\u629e\u304c\u6b63\u3057\u3044C\u8a00\u8a9e\u306e\u66f8\u304d\u65b9\u3067\u3059\u3002<\/div>\n<\/div>\n\n\n\n<div style=\"margin:48px 0 8px;text-align:center;\">\n  <a href=\"https:\/\/aikanri.genai-ai.co.jp\/?utm_source=blog&utm_medium=article&utm_campaign=cc-c-absolute-value&utm_content=h2-banner\" target=\"_blank\" rel=\"noopener\">\n    <img decoding=\"async\" src=\"https:\/\/genai-ai.co.jp\/ai-kanri\/wp-content\/uploads\/2026\/04\/cta_blog.jpg\" alt=\"Claude Code\u3092\u7d4c\u55b6\u306b\u6d3b\u304b\u3057\u305f\u3044\u65b9\u3078 \u2014 AI\u9b3c\u7ba1\u7406\" style=\"width:100%;max-width:800px;height:auto;border-radius:8px;display:inline-block;\">\n  <\/a>\n<\/div>\n\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;\">LONG TYPE<\/span>\n  <span class=\"section-title\" style=\"display:block;\">labs\u30fbllabs\u95a2\u6570\uff08long\/long long\u578b\uff09<\/span>\n  <span class=\"section-desc\">\u5927\u304d\u306a\u6574\u6570\u5024\u306e\u7d76\u5bfe\u5024\u3092\u6b63\u78ba\u306b\u6c42\u3081\u308b\u65b9\u6cd5<\/span>\n<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">int\u578b\u306e\u7bc4\u56f2\uff08\u7d04\u00b121\u5104\uff09\u3092\u8d85\u3048\u308b\u6574\u6570\u5024\u3092\u6271\u3046\u5834\u5408\u306f\u3001<strong>labs\uff08long\u578b\u7528\uff09<\/strong>\u307e\u305f\u306f<strong>llabs\uff08long long\u578b\u7528\uff09<\/strong>\u3092\u4f7f\u3046\u5fc5\u8981\u304c\u3042\u308a\u307e\u3059\u3002\u3069\u3061\u3089\u3082 <code>&lt;stdlib.h&gt;<\/code> \u306b\u542b\u307e\u308c\u3066\u304a\u308a\u3001abs \u3068\u540c\u69d8\u306b\u30a4\u30f3\u30af\u30eb\u30fc\u30c9\u3059\u308b\u3060\u3051\u3067\u4f7f\u7528\u3067\u304d\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>long\u578b<\/strong>\uff1aC\u8a00\u8a9e\u306e\u62e1\u5f35\u6574\u6570\u578b\u300232\u30d3\u30c3\u30c8\u74b0\u5883\u3067\u306f int \u3068\u540c\u305832\u30d3\u30c3\u30c8\u5e45\u306e\u3053\u3068\u3082\u3042\u308b\u304c\u300164\u30d3\u30c3\u30c8 Linux\/macOS\u74b0\u5883\u3067\u306flong\u578b\u306f64\u30d3\u30c3\u30c8\uff08-9,223,372,036,854,775,808 \u301c 9,223,372,036,854,775,807\uff09\u3068\u306a\u308b\u3002Windows\u306e64\u30d3\u30c3\u30c8\u74b0\u5883\u3067\u306flong\u578b\u306f32\u30d3\u30c3\u30c8\u306e\u307e\u307e\u3002\u3053\u306e\u74b0\u5883\u4f9d\u5b58\u6027\u306e\u305f\u3081\u3001\u5927\u304d\u306a\u6574\u6570\u306b\u306flong long\u3092\u4f7f\u3046\u3053\u3068\u304c\u63a8\u5968\u3055\u308c\u308b\u3002labs()\u306f\u3053\u306elong\u578b\u306e\u7d76\u5bfe\u5024\u3092\u8fd4\u3059\u95a2\u6570\u3002<\/p>\n<\/div>\n\n\n\n<p class=\"wp-block-paragraph\">\u4ee5\u4e0b\u306blabs\u30fbllaabs\u4e21\u95a2\u6570\u306e\u5b9f\u8df5\u7684\u306a\u30b5\u30f3\u30d7\u30eb\u3092\u793a\u3057\u307e\u3059\u3002<\/p>\n\n\n\n<pre style=\"background:#1e1e1e;color:#d4d4d4;padding:20px 24px;border-radius:8px;overflow-x:auto;line-height:1.7;margin:20px 0;font-size:14px;\"><code>#include &lt;stdio.h&gt;\n#include &lt;stdlib.h&gt;  \/* labs(), llabs() \u3092\u4f7f\u3046\u305f\u3081\u306b\u5fc5\u8981 *\/\n\nint main(void) {\n    long a = -1234567890L;\n    long b = 9876543210L;\n\n    printf(\"labs(%ld) = %ld\\n\", a, labs(a));   \/* 1234567890 *\/\n    printf(\"labs(%ld) = %ld\\n\", b, labs(b));   \/* 9876543210 *\/\n\n    long long c = -9876543210123LL;\n    long long d = 1000000000000LL;\n\n    printf(\"llabs(%lld) = %lld\\n\", c, llabs(c)); \/* 9876543210123 *\/\n    printf(\"llabs(%lld) = %lld\\n\", d, llabs(d)); \/* 1000000000000 *\/\n\n    \/* long long\u578b\u3067\u306e\u5dee\u5206\u7d76\u5bfe\u5024\u8a08\u7b97\uff08\u5927\u304d\u306a\u30d5\u30a1\u30a4\u30eb\u30b5\u30a4\u30ba\u6bd4\u8f03\u7b49\u306b\u6709\u7528\uff09 *\/\n    long long file1_size = 5368709120LL;   \/* 5GB *\/\n    long long file2_size = 3221225472LL;   \/* 3GB *\/\n    long long diff = llabs(file1_size - file2_size);\n    printf(\"\u30d5\u30a1\u30a4\u30eb\u30b5\u30a4\u30ba\u5dee: %lld \u30d0\u30a4\u30c8\\n\", diff);  \/* 2147483648 *\/\n\n    return 0;\n}<\/code><\/pre>\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\">\u30d5\u30a1\u30a4\u30eb\u30b5\u30a4\u30ba\u3001\u30cd\u30c3\u30c8\u30ef\u30fc\u30af\u8ee2\u9001\u91cf\u3001\u30bf\u30a4\u30e0\u30b9\u30bf\u30f3\u30d7\u306e\u5dee\u5206\u306a\u3069\u3001\u73fe\u4ee3\u306e\u30b7\u30b9\u30c6\u30e0\u958b\u767a\u3067\u306flong long\u578b\u304c\u5fc5\u9808\u306e\u5834\u9762\u304c\u591a\u304f\u306a\u3063\u3066\u3044\u307e\u3059\u3002\u300cint\u3067\u8db3\u308a\u308b\u3060\u308d\u3046\u300d\u3068\u3044\u3046\u5148\u5165\u89b3\u304c\u5f8c\u3067\u5927\u304d\u306a\u554f\u984c\u306b\u306a\u308b\u3053\u3068\u304c\u3042\u308a\u307e\u3059\u3002<\/div>\n<\/div>\n\n\n\n<p class=\"wp-block-paragraph\">labs \u3068llabs \u306e\u4f7f\u3044\u5206\u3051\u306f\u3001\u5909\u6570\u306e\u578b\u306b\u5b8c\u5168\u306b\u4e00\u81f4\u3055\u305b\u308b\u3053\u3068\u304c\u91cd\u8981\u3067\u3059\u3002\u578b\u304c\u4e00\u81f4\u3057\u3066\u3044\u306a\u3044\u3068\u3001\u6697\u9ed9\u306e\u578b\u5909\u63db\u304c\u884c\u308f\u308c\u3066\u8a08\u7b97\u7cbe\u5ea6\u304c\u5931\u308f\u308c\u308b\u53ef\u80fd\u6027\u304c\u3042\u308a\u307e\u3059\u3002\u4ee5\u4e0b\u306e\u30d5\u30ed\u30fc\u56f3\u3067\u6574\u6570\u578b\u306e\u95a2\u6570\u9078\u629e\u3092\u6574\u7406\u3057\u307e\u3057\u3087\u3046\u3002<\/p>\n\n\n\n<div class=\"g-flow-row\" style=\"margin:24px 0;\">\n  <div class=\"g-flow-item\">int\u578b\u306e\u5024<\/div>\n  <div class=\"g-flow-item\">abs() \u3092\u4f7f\u7528<\/div>\n  <div class=\"g-flow-item\">\u2192 long\u578b\u306e\u5024<\/div>\n  <div class=\"g-flow-item\">labs() \u3092\u4f7f\u7528<\/div>\n  <div class=\"g-flow-item\">\u2192 long long\u578b\u306e\u5024<\/div>\n  <div class=\"g-flow-item\">llabs() \u3092\u4f7f\u7528<\/div>\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;\">long\u306e\u30b5\u30a4\u30ba\u306f\u74b0\u5883\u4f9d\u5b58<\/strong>\n  <\/div>\n  <p style=\"margin:0;font-size:15px;line-height:1.8;color:#333;\">long\u578b\u306e\u30d3\u30c3\u30c8\u5e45\u306f\u51e6\u7406\u7cfb\u30fb\u30d7\u30e9\u30c3\u30c8\u30d5\u30a9\u30fc\u30e0\u306b\u3088\u3063\u3066\u7570\u306a\u308a\u307e\u3059\u3002Windows\u306e64\u30d3\u30c3\u30c8\u74b0\u5883\u3067\u306flong\u578b\u306f32\u30d3\u30c3\u30c8\uff08int\u3068\u540c\u3058\u5e45\uff09\u3067\u3059\u304c\u300164\u30d3\u30c3\u30c8\u306eLinux\u30fbmacOS\u74b0\u5883\u3067\u306f64\u30d3\u30c3\u30c8\u3067\u3059\u3002\u3053\u306e\u9055\u3044\u3092\u7121\u8996\u3059\u308b\u3068\u3001long\u578b\u306b\u5927\u304d\u306a\u5024\u3092\u4ee3\u5165\u3057\u305f\u3064\u3082\u308a\u304c\u30aa\u30fc\u30d0\u30fc\u30d5\u30ed\u30fc\u3059\u308b\u53ef\u80fd\u6027\u304c\u3042\u308a\u307e\u3059\u3002\u79fb\u690d\u6027\u3092\u91cd\u8996\u3059\u308b\u30b3\u30fc\u30c9\u3067\u306f\u3001<code>&lt;stdint.h&gt;<\/code>\u306eint32_t\u30fbint64_t\u3092\u4f7f\u3044\u3001\u5bfe\u5fdc\u3059\u308babs\u95a2\u6570\u306fimaxabs\uff08<code>&lt;inttypes.h&gt;<\/code>\uff09\u3092\u691c\u8a0e\u3057\u3066\u304f\u3060\u3055\u3044\u3002<\/p>\n<\/div>\n\n\n\n<div style=\"margin:48px 0 8px;text-align:center;\">\n  <a href=\"https:\/\/aikanri.genai-ai.co.jp\/?utm_source=blog&utm_medium=article&utm_campaign=cc-c-absolute-value&utm_content=h2-banner\" target=\"_blank\" rel=\"noopener\">\n    <img decoding=\"async\" src=\"https:\/\/genai-ai.co.jp\/ai-kanri\/wp-content\/uploads\/2026\/04\/cta_blog.jpg\" alt=\"Claude Code\u3092\u7d4c\u55b6\u306b\u6d3b\u304b\u3057\u305f\u3044\u65b9\u3078 \u2014 AI\u9b3c\u7ba1\u7406\" style=\"width:100%;max-width:800px;height:auto;border-radius:8px;display:inline-block;\">\n  <\/a>\n<\/div>\n\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;\">FLOAT TYPE<\/span>\n  <span class=\"section-title\" style=\"display:block;\">fabs\u30fbfabsf\u95a2\u6570\uff08double\/float\u578b\uff09<\/span>\n  <span class=\"section-desc\">\u6d6e\u52d5\u5c0f\u6570\u70b9\u6570\u306e\u7d76\u5bfe\u5024\u306fmath.h\u306e\u95a2\u6570\u3092\u4f7f\u3046<\/span>\n<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u6d6e\u52d5\u5c0f\u6570\u70b9\u6570\uff08\u5c0f\u6570\u3092\u542b\u3080\u5b9f\u6570\uff09\u306e\u7d76\u5bfe\u5024\u3092\u6c42\u3081\u308b\u969b\u306f\u3001<strong>fabs\uff08double\u578b\u7528\uff09<\/strong>\u307e\u305f\u306f<strong>fabsf\uff08float\u578b\u7528\uff09<\/strong>\u3092\u4f7f\u3044\u307e\u3059\u3002\u3053\u308c\u3089\u306f <code>&lt;math.h&gt;<\/code> \u306b\u5ba3\u8a00\u3055\u308c\u3066\u304a\u308a\u3001\u30b3\u30f3\u30d1\u30a4\u30eb\u6642\u306b\u306f <code>-lm<\/code> \u30aa\u30d7\u30b7\u30e7\u30f3\u3067\u306e\u6570\u5b66\u30e9\u30a4\u30d6\u30e9\u30ea\u306e\u30ea\u30f3\u30af\u304c\u5fc5\u8981\u306a\u74b0\u5883\u304c\u3042\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>double\u578b<\/strong>\uff1aC\u8a00\u8a9e\u306e\u500d\u7cbe\u5ea6\u6d6e\u52d5\u5c0f\u6570\u70b9\u578b\u3002IEEE 754\u898f\u683c\u306b\u57fa\u3065\u304f64\u30d3\u30c3\u30c8\u306e\u6d6e\u52d5\u5c0f\u6570\u70b9\u6570\u3002\u7cbe\u5ea6\u306f\u7d0415\u301c16\u6841\u306e\u6709\u52b9\u6570\u5b57\u3002C\u8a00\u8a9e\u306b\u304a\u3044\u3066\u6d6e\u52d5\u5c0f\u6570\u70b9\u30ea\u30c6\u30e9\u30eb\u306e\u30c7\u30d5\u30a9\u30eb\u30c8\u578b\u306fdouble\u3067\u3042\u308a\u30013.14\u30842.71828\u306a\u3069\u306f\u81ea\u52d5\u7684\u306bdouble\u578b\u3068\u3057\u3066\u6271\u308f\u308c\u308b\u3002\u79d1\u5b66\u6280\u8853\u8a08\u7b97\u3001\u91d1\u878d\u8a08\u7b97\u306a\u3069\u9ad8\u7cbe\u5ea6\u304c\u5fc5\u8981\u306a\u5834\u9762\u3067\u4f7f\u7528\u3055\u308c\u308b\u3002fabs()\u306fdouble\u578b\u306e\u7d76\u5bfe\u5024\u3092\u8fd4\u3059\u95a2\u6570\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>float\u578b<\/strong>\uff1aC\u8a00\u8a9e\u306e\u5358\u7cbe\u5ea6\u6d6e\u52d5\u5c0f\u6570\u70b9\u578b\u3002IEEE 754\u898f\u683c\u306b\u57fa\u3065\u304f32\u30d3\u30c3\u30c8\u306e\u6d6e\u52d5\u5c0f\u6570\u70b9\u6570\u3002\u7cbe\u5ea6\u306f\u7d046\u301c7\u6841\u306e\u6709\u52b9\u6570\u5b57\u3002double\u3088\u308a\u7cbe\u5ea6\u306f\u4f4e\u3044\u304c\u3001\u30e1\u30e2\u30ea\u4f7f\u7528\u91cf\u304c\u534a\u5206\u3067\u51e6\u7406\u304c\u9ad8\u901f\u306a\u305f\u3081\u3001\u7d44\u307f\u8fbc\u307f\u30b7\u30b9\u30c6\u30e0\u3084\u30b0\u30e9\u30d5\u30a3\u30c3\u30af\u30b9\u51e6\u7406\uff083D\u8a08\u7b97\u7b49\uff09\u3067\u306f\u591a\u7528\u3055\u308c\u308b\u3002float\u578b\u30ea\u30c6\u30e9\u30eb\u3092\u793a\u3059\u306b\u306f 3.14f \u306e\u3088\u3046\u306b\u672b\u5c3e\u306bf\u3092\u3064\u3051\u308b\u3002fabsf()\u306ffloat\u578b\u306e\u7d76\u5bfe\u5024\u3092\u8fd4\u3059\u95a2\u6570\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>math.h<\/strong>\uff1aC\u8a00\u8a9e\u306e\u6570\u5b66\u30e9\u30a4\u30d6\u30e9\u30ea\u30d8\u30c3\u30c0\u3002sin\/cos\/tan\uff08\u4e09\u89d2\u95a2\u6570\uff09\u3001sqrt\uff08\u5e73\u65b9\u6839\uff09\u3001pow\uff08\u3079\u304d\u4e57\uff09\u3001log\uff08\u5bfe\u6570\uff09\u3001fabs\/fabsf\uff08\u7d76\u5bfe\u5024\uff09\u306a\u3069\u3001\u6570\u5b66\u7684\u306a\u8a08\u7b97\u95a2\u6570\u304c\u5ba3\u8a00\u3055\u308c\u3066\u3044\u308b\u3002<code>#include &lt;math.h&gt;<\/code>\u3067\u30a4\u30f3\u30af\u30eb\u30fc\u30c9\u3057\u3066\u4f7f\u3046\u3002GCC\u7b49\u306e\u74b0\u5883\u3067\u306f\u30b3\u30f3\u30d1\u30a4\u30eb\u6642\u306b<code>-lm<\/code>\u30aa\u30d7\u30b7\u30e7\u30f3\u3092\u8ffd\u52a0\u3057\u3066\u6570\u5b66\u30e9\u30a4\u30d6\u30e9\u30ea\u3092\u30ea\u30f3\u30af\u3059\u308b\u5fc5\u8981\u304c\u3042\u308b\u5834\u5408\u304c\u3042\u308b\u3002<\/p>\n<\/div>\n\n\n\n<p class=\"wp-block-paragraph\">\u4ee5\u4e0b\u306e\u30b5\u30f3\u30d7\u30eb\u3067\u306f fabs \u3068 fabsf \u306e\u4e21\u65b9\u3092\u5b9f\u969b\u306b\u4f7f\u3044\u3001double\u578b\u3068float\u578b\u305d\u308c\u305e\u308c\u3067\u7d76\u5bfe\u5024\u3092\u8a08\u7b97\u3059\u308b\u65b9\u6cd5\u3092\u793a\u3057\u307e\u3059\u3002<\/p>\n\n\n\n<pre style=\"background:#1e1e1e;color:#d4d4d4;padding:20px 24px;border-radius:8px;overflow-x:auto;line-height:1.7;margin:20px 0;font-size:14px;\"><code>#include &lt;stdio.h&gt;\n#include &lt;math.h&gt;   \/* fabs(), fabsf() \u3092\u4f7f\u3046\u305f\u3081\u306b\u5fc5\u8981 *\/\n\nint main(void) {\n    \/* double\u578b\u306e\u7d76\u5bfe\u5024: fabs() *\/\n    double d1 = -3.141592653589793;\n    double d2 = 2.718281828459045;\n    double d3 = -0.0;\n\n    printf(\"fabs(%f) = %f\\n\", d1, fabs(d1));  \/* 3.141593 *\/\n    printf(\"fabs(%f) = %f\\n\", d2, fabs(d2));  \/* 2.718282 *\/\n    printf(\"fabs(%f) = %f\\n\", d3, fabs(d3));  \/* 0.000000 *\/\n\n    \/* float\u578b\u306e\u7d76\u5bfe\u5024: fabsf() *\/\n    float f1 = -1.5f;\n    float f2 = 0.001f;\n    float f3 = -100.0f;\n\n    printf(\"fabsf(%f) = %f\\n\", f1, fabsf(f1));  \/* 1.500000 *\/\n    printf(\"fabsf(%f) = %f\\n\", f2, fabsf(f2));  \/* 0.001000 *\/\n    printf(\"fabsf(%f) = %f\\n\", f3, fabsf(f3));  \/* 100.000000 *\/\n\n    \/* \u8aa4\u5dee\u306e\u7d76\u5bfe\u5024\u30c1\u30a7\u30c3\u30af\uff08\u6570\u5024\u8a08\u7b97\u3067\u306e\u5178\u578b\u7684\u306a\u4f7f\u7528\u4f8b\uff09 *\/\n    double expected = 1.0 \/ 3.0;\n    double computed = 0.333333;\n    double error = fabs(expected - computed);\n    printf(\"\u8aa4\u5dee\u306e\u7d76\u5bfe\u5024: %e\\n\", error);\n\n    return 0;\n}<\/code><\/pre>\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\">double\u578b\u3092\u4f7f\u3046\u5834\u5408\u306ffabs()\u3001float\u578b\u3092\u4f7f\u3046\u5834\u5408\u306ffabsf()\u3092\u4f7f\u3046\u306e\u304c\u57fa\u672c\u30eb\u30fc\u30eb\u3067\u3059\u3002double\u578b\u306e\u5024\u306bfabsf()\u3092\u4f7f\u3046\u3068\u7cbe\u5ea6\u304c\u843d\u3061\u308b\u5834\u5408\u304c\u3042\u308b\u306e\u3067\u6ce8\u610f\u3057\u3066\u304f\u3060\u3055\u3044\u3002<\/div>\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;\">-lm \u30aa\u30d7\u30b7\u30e7\u30f3\u3092\u5fd8\u308c\u308b\u3068\u30ea\u30f3\u30af\u30a8\u30e9\u30fc\u306b\u306a\u308b<\/strong>\n  <\/div>\n  <p style=\"margin:0;font-size:15px;line-height:1.8;color:#333;\">GCC\uff08Linux\/macOS\u74b0\u5883\uff09\u3067\u306f\u3001math.h\u306e\u95a2\u6570\u3092\u4f7f\u3046\u305f\u3081\u306b\u30b3\u30f3\u30d1\u30a4\u30eb\u6642\u306b <code>-lm<\/code> \u30aa\u30d7\u30b7\u30e7\u30f3\u3092\u8ffd\u52a0\u3059\u308b\u5fc5\u8981\u304c\u3042\u308a\u307e\u3059\u3002<code>gcc myprogram.c -o myprogram -lm<\/code> \u306e\u3088\u3046\u306b\u8a18\u8ff0\u3057\u307e\u3059\u3002\u3053\u306e\u30aa\u30d7\u30b7\u30e7\u30f3\u3092\u5fd8\u308c\u308b\u3068\u300cundefined reference to `fabs'\u300d\u306e\u3088\u3046\u306a\u30ea\u30f3\u30af\u30a8\u30e9\u30fc\u304c\u767a\u751f\u3057\u307e\u3059\u3002\u4e00\u65b9\u3001Windows\u306e\u591a\u304f\u306e\u958b\u767a\u74b0\u5883\uff08MinGW, Visual Studio\u7b49\uff09\u3067\u306f -lm \u304c\u4e0d\u8981\u306a\u5834\u5408\u3082\u3042\u308a\u307e\u3059\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;\">C99\u4ee5\u964d\u306etgmath.h\u3092\u4f7f\u3046\u65b9\u6cd5<\/strong>\n  <\/div>\n  <p style=\"margin:0;font-size:15px;line-height:1.8;color:#333;\">C99\u898f\u683c\u4ee5\u964d\u3067\u306f <code>&lt;tgmath.h&gt;<\/code>\uff08type-generic math\uff09\u3092\u30a4\u30f3\u30af\u30eb\u30fc\u30c9\u3059\u308b\u3053\u3068\u3067\u3001\u5f15\u6570\u306e\u578b\u306b\u5fdc\u3058\u3066fabs\/fabsf\/fabsl\u3092\u81ea\u52d5\u9078\u629e\u3059\u308b\u30de\u30af\u30ed\u3068\u3057\u3066 abs\/fabs \u3092\u4f7f\u3048\u307e\u3059\u3002\u79fb\u690d\u6027\u306e\u9ad8\u3044\u30b3\u30fc\u30c9\u3092\u66f8\u304f\u5834\u5408\u3001C99\u4ee5\u964d\u306e\u74b0\u5883\u9650\u5b9a\u306a\u3089tgmath.h\u3082\u9078\u629e\u80a2\u306b\u306a\u308a\u307e\u3059\u3002\u305f\u3060\u3057C++\u3067\u306f\u30aa\u30fc\u30d0\u30fc\u30ed\u30fc\u30c9\u304c\u4f7f\u3048\u308b\u305f\u3081\u3001std::abs\u3060\u3051\u3067\u5168\u578b\u306b\u5bfe\u5fdc\u3067\u304d\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\">\u7d44\u307f\u8fbc\u307f\u7cfb\u306e\u73fe\u5834\u3067\u3088\u304f\u898b\u308b\u9593\u9055\u3044\u306f\u3001double\u578b\u5909\u6570\u306bfabsf()\u3092\u4f7f\u3046\u3053\u3068\u3067\u3059\u3002float\u578b\u306f32\u30d3\u30c3\u30c8\u306a\u306e\u3067double\u306e\u7cbe\u5ea6\uff0864\u30d3\u30c3\u30c8\uff09\u304c\u5931\u308f\u308c\u307e\u3059\u3002\u7279\u306b\u30bb\u30f3\u30b5\u30fc\u30c7\u30fc\u30bf\u306e\u51e6\u7406\u3067\u306f\u7cbe\u5ea6\u306e\u9055\u3044\u304c\u5236\u5fa1\u54c1\u8cea\u306b\u76f4\u7d50\u3059\u308b\u306e\u3067\u8981\u6ce8\u610f\u3067\u3059\u3002<\/div>\n<\/div>\n\n\n\n<div style=\"margin:48px 0 8px;text-align:center;\">\n  <a href=\"https:\/\/aikanri.genai-ai.co.jp\/?utm_source=blog&utm_medium=article&utm_campaign=cc-c-absolute-value&utm_content=h2-banner\" target=\"_blank\" rel=\"noopener\">\n    <img decoding=\"async\" src=\"https:\/\/genai-ai.co.jp\/ai-kanri\/wp-content\/uploads\/2026\/04\/cta_blog.jpg\" alt=\"Claude Code\u3092\u7d4c\u55b6\u306b\u6d3b\u304b\u3057\u305f\u3044\u65b9\u3078 \u2014 AI\u9b3c\u7ba1\u7406\" style=\"width:100%;max-width:800px;height:auto;border-radius:8px;display:inline-block;\">\n  <\/a>\n<\/div>\n\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;\">SELECTION GUIDE<\/span>\n  <span class=\"section-title\" style=\"display:block;\">\u30c7\u30fc\u30bf\u578b\u5225\u306e\u95a2\u6570\u9078\u629e\u30ac\u30a4\u30c9<\/span>\n  <span class=\"section-desc\">\u578b\u3092\u898b\u305f\u77ac\u9593\u306b\u6b63\u3057\u3044\u95a2\u6570\u304c\u9078\u3079\u308b\u3088\u3046\u306b\u306a\u308b<\/span>\n<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">C\u8a00\u8a9e\u306e\u7d76\u5bfe\u5024\u95a2\u6570\u306f5\u7a2e\u985e\uff08abs\u30fblabs\u30fbllabs\u30fbfabs\u30fbfabsf\uff09\u3042\u308a\u3001\u305d\u308c\u305e\u308c\u304c\u7279\u5b9a\u306e\u30c7\u30fc\u30bf\u578b\u306b\u5bfe\u3057\u3066\u6700\u9069\u5316\u3055\u308c\u3066\u3044\u307e\u3059\u3002\u4ee5\u4e0b\u306e\u610f\u601d\u6c7a\u5b9a\u30d5\u30ed\u30fc\u3092\u53c2\u8003\u306b\u3001\u30b3\u30fc\u30c9\u4e2d\u306e\u5909\u6570\u306e\u578b\u306b\u5fdc\u3058\u305f\u6b63\u3057\u3044\u95a2\u6570\u3092\u9078\u3093\u3067\u304f\u3060\u3055\u3044\u3002<\/p>\n\n\n\n<div class=\"g-flow-row\" style=\"margin:24px 0;\">\n  <div class=\"g-flow-item\">\u5909\u6570\u306e\u578b\u3092\u78ba\u8a8d<\/div>\n  <div class=\"g-flow-item\">int \u2192 abs()<\/div>\n  <div class=\"g-flow-item\">long \u2192 labs()<\/div>\n  <div class=\"g-flow-item\">long long \u2192 llabs()<\/div>\n  <div class=\"g-flow-item\">double \u2192 fabs()<\/div>\n  <div class=\"g-flow-item\">float \u2192 fabsf()<\/div>\n<\/div>\n\n\n\n<p class=\"wp-block-paragraph\">\u3088\u308a\u8a73\u7d30\u306a\u60c5\u5831\u3092\u4ee5\u4e0b\u306e\u6bd4\u8f03\u8868\u306b\u307e\u3068\u3081\u307e\u3057\u305f\u3002\u30d8\u30c3\u30c0\u30d5\u30a1\u30a4\u30eb\u3001\u5f15\u6570\u578b\u3001\u623b\u308a\u5024\u578b\u3001\u30b3\u30f3\u30d1\u30a4\u30eb\u30aa\u30d7\u30b7\u30e7\u30f3\u306e4\u70b9\u3092\u4e00\u89a7\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<div style=\"overflow-x:auto;margin:20px 0;\">\n<table style=\"width:100%;border-collapse:collapse;font-size:14px;\">\n  <thead>\n    <tr style=\"background:linear-gradient(135deg,#1a1a1a,#2a1015);color:#fff;\">\n      <th style=\"padding:12px 16px;text-align:left;border:1px solid #444;\">\u95a2\u6570\u540d<\/th>\n      <th style=\"padding:12px 16px;text-align:left;border:1px solid #444;\">\u5bfe\u8c61\u578b<\/th>\n      <th style=\"padding:12px 16px;text-align:left;border:1px solid #444;\">\u5f15\u6570\u578b<\/th>\n      <th style=\"padding:12px 16px;text-align:left;border:1px solid #444;\">\u623b\u308a\u5024\u578b<\/th>\n      <th style=\"padding:12px 16px;text-align:left;border:1px solid #444;\">\u30d8\u30c3\u30c0<\/th>\n      <th style=\"padding:12px 16px;text-align:left;border:1px solid #444;\">\u30b3\u30f3\u30d1\u30a4\u30eb\u30aa\u30d7\u30b7\u30e7\u30f3<\/th>\n    <\/tr>\n  <\/thead>\n  <tbody>\n    <tr style=\"background:#fff;\">\n      <td style=\"padding:10px 16px;border:1px solid #ddd;\"><strong>abs()<\/strong><\/td>\n      <td style=\"padding:10px 16px;border:1px solid #ddd;\">int\u578b\u6574\u6570<\/td>\n      <td style=\"padding:10px 16px;border:1px solid #ddd;\">int<\/td>\n      <td style=\"padding:10px 16px;border:1px solid #ddd;\">int<\/td>\n      <td style=\"padding:10px 16px;border:1px solid #ddd;\"><code>&lt;stdlib.h&gt;<\/code><\/td>\n      <td style=\"padding:10px 16px;border:1px solid #ddd;\">\u4e0d\u8981<\/td>\n    <\/tr>\n    <tr style=\"background:#f8f9fa;\">\n      <td style=\"padding:10px 16px;border:1px solid #ddd;\"><strong>labs()<\/strong><\/td>\n      <td style=\"padding:10px 16px;border:1px solid #ddd;\">long\u578b\u6574\u6570<\/td>\n      <td style=\"padding:10px 16px;border:1px solid #ddd;\">long<\/td>\n      <td style=\"padding:10px 16px;border:1px solid #ddd;\">long<\/td>\n      <td style=\"padding:10px 16px;border:1px solid #ddd;\"><code>&lt;stdlib.h&gt;<\/code><\/td>\n      <td style=\"padding:10px 16px;border:1px solid #ddd;\">\u4e0d\u8981<\/td>\n    <\/tr>\n    <tr style=\"background:#fff;\">\n      <td style=\"padding:10px 16px;border:1px solid #ddd;\"><strong>llabs()<\/strong><\/td>\n      <td style=\"padding:10px 16px;border:1px solid #ddd;\">long long\u578b\u6574\u6570<\/td>\n      <td style=\"padding:10px 16px;border:1px solid #ddd;\">long long<\/td>\n      <td style=\"padding:10px 16px;border:1px solid #ddd;\">long long<\/td>\n      <td style=\"padding:10px 16px;border:1px solid #ddd;\"><code>&lt;stdlib.h&gt;<\/code><\/td>\n      <td style=\"padding:10px 16px;border:1px solid #ddd;\">\u4e0d\u8981\uff08C99\u4ee5\u964d\uff09<\/td>\n    <\/tr>\n    <tr style=\"background:#f8f9fa;\">\n      <td style=\"padding:10px 16px;border:1px solid #ddd;\"><strong>fabs()<\/strong><\/td>\n      <td style=\"padding:10px 16px;border:1px solid #ddd;\">double\u578b\u5b9f\u6570<\/td>\n      <td style=\"padding:10px 16px;border:1px solid #ddd;\">double<\/td>\n      <td style=\"padding:10px 16px;border:1px solid #ddd;\">double<\/td>\n      <td style=\"padding:10px 16px;border:1px solid #ddd;\"><code>&lt;math.h&gt;<\/code><\/td>\n      <td style=\"padding:10px 16px;border:1px solid #ddd;\">-lm\uff08\u74b0\u5883\u4f9d\u5b58\uff09<\/td>\n    <\/tr>\n    <tr style=\"background:#fff;\">\n      <td style=\"padding:10px 16px;border:1px solid #ddd;\"><strong>fabsf()<\/strong><\/td>\n      <td style=\"padding:10px 16px;border:1px solid #ddd;\">float\u578b\u5b9f\u6570<\/td>\n      <td style=\"padding:10px 16px;border:1px solid #ddd;\">float<\/td>\n      <td style=\"padding:10px 16px;border:1px solid #ddd;\">float<\/td>\n      <td style=\"padding:10px 16px;border:1px solid #ddd;\"><code>&lt;math.h&gt;<\/code><\/td>\n      <td style=\"padding:10px 16px;border:1px solid #ddd;\">-lm\uff08\u74b0\u5883\u4f9d\u5b58\uff09<\/td>\n    <\/tr>\n  <\/tbody>\n<\/table>\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>abs()<\/strong>\uff1aint\u578b\u306e\u307f\u3002stdlib.h\u3092\u30a4\u30f3\u30af\u30eb\u30fc\u30c9\u3002\u6700\u3082\u4f7f\u7528\u983b\u5ea6\u304c\u9ad8\u3044<\/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>labs()<\/strong>\uff1along\u578b\u5c02\u7528\u3002stdlib.h\u3092\u30a4\u30f3\u30af\u30eb\u30fc\u30c9\u3002\u74b0\u5883\u306b\u3088\u308aint\u3068\u540c\u30b5\u30a4\u30ba\u306e\u3053\u3068\u3082<\/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>llabs()<\/strong>\uff1along long\u578b\u5c02\u7528\u3002stdlib.h\u3092\u30a4\u30f3\u30af\u30eb\u30fc\u30c9\u3002C99\u4ee5\u964d\u3067\u5229\u7528\u53ef\u80fd<\/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>fabs()<\/strong>\uff1adouble\u578b\u5c02\u7528\u3002math.h\u3092\u30a4\u30f3\u30af\u30eb\u30fc\u30c9\u3002Linux\u3067\u306f-lm\u304c\u5fc5\u8981\u306a\u3053\u3068\u3082<\/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>fabsf()<\/strong>\uff1afloat\u578b\u5c02\u7528\u3002math.h\u3092\u30a4\u30f3\u30af\u30eb\u30fc\u30c9\u3002\u7d44\u307f\u8fbc\u307f\u7cfb\u3067\u3088\u304f\u4f7f\u3046<\/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\">\u3053\u306e\u8868\u3092\u898b\u306a\u304c\u3089\u300c\u81ea\u5206\u304c\u4eca\u64cd\u4f5c\u3057\u3066\u3044\u308b\u5909\u6570\u306e\u578b\u306f\u4f55\u304b\uff1f\u300d\u3068\u78ba\u8a8d\u3059\u308b\u7656\u3092\u3064\u3051\u3066\u304f\u3060\u3055\u3044\u3002\u578b\u304c\u898b\u3048\u3066\u3044\u308c\u3070\u6b63\u3057\u3044\u95a2\u6570\u3092\u9078\u3076\u306e\u306f\u96e3\u3057\u304f\u3042\u308a\u307e\u305b\u3093\u3002<\/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;\">C11\u4ee5\u964d\u306e_Generic\u69cb\u6587\u306b\u3088\u308b\u6c4e\u7528\u5316<\/strong>\n  <\/div>\n  <p style=\"margin:0;font-size:15px;line-height:1.8;color:#333;\">C11\u898f\u683c\u4ee5\u964d\u3067\u306f _Generic \u69cb\u6587\u3092\u4f7f\u3063\u3066\u578b\u306b\u5fdc\u3058\u305f\u95a2\u6570\u3092\u81ea\u52d5\u9078\u629e\u3059\u308b\u30de\u30af\u30ed\u3092\u81ea\u4f5c\u3067\u304d\u307e\u3059\u3002\u305f\u3068\u3048\u3070 <code>#define ABS(x) _Generic((x), int: abs, long: labs, long long: llabs, float: fabsf, double: fabs)(x)<\/code> \u306e\u3088\u3046\u306b\u5b9a\u7fa9\u3059\u308b\u3068\u3001\u578b\u306b\u95a2\u308f\u3089\u305a ABS(x) \u3067\u547c\u3073\u51fa\u305b\u307e\u3059\u3002\u305f\u3060\u3057\u53ef\u8aad\u6027\u304c\u4e0b\u304c\u308b\u305f\u3081\u3001\u30c1\u30fc\u30e0\u306e\u65b9\u91dd\u306b\u5408\u308f\u305b\u3066\u5224\u65ad\u3057\u3066\u304f\u3060\u3055\u3044\u3002<\/p>\n<\/div>\n\n\n\n<div style=\"margin:48px 0 8px;text-align:center;\">\n  <a href=\"https:\/\/aikanri.genai-ai.co.jp\/?utm_source=blog&utm_medium=article&utm_campaign=cc-c-absolute-value&utm_content=h2-banner\" target=\"_blank\" rel=\"noopener\">\n    <img decoding=\"async\" src=\"https:\/\/genai-ai.co.jp\/ai-kanri\/wp-content\/uploads\/2026\/04\/cta_blog.jpg\" alt=\"Claude Code\u3092\u7d4c\u55b6\u306b\u6d3b\u304b\u3057\u305f\u3044\u65b9\u3078 \u2014 AI\u9b3c\u7ba1\u7406\" style=\"width:100%;max-width:800px;height:auto;border-radius:8px;display:inline-block;\">\n  <\/a>\n<\/div>\n\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;\">CUSTOM IMPL<\/span>\n  <span class=\"section-title\" style=\"display:block;\">if-else\u30fb\u4e09\u9805\u6f14\u7b97\u5b50\u3067\u81ea\u4f5c\u3059\u308b\u65b9\u6cd5<\/span>\n  <span class=\"section-desc\">\u6a19\u6e96\u95a2\u6570\u3092\u4f7f\u308f\u305a\u306b\u7d76\u5bfe\u5024\u3092\u5b9f\u88c5\u3059\u308b\u30d1\u30bf\u30fc\u30f3\u96c6<\/span>\n<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u6a19\u6e96\u30e9\u30a4\u30d6\u30e9\u30ea\u306e\u7d76\u5bfe\u5024\u95a2\u6570\u3092\u4f7f\u308f\u305a\u3001\u81ea\u524d\u3067\u5b9f\u88c5\u3059\u308b\u30d1\u30bf\u30fc\u30f3\u3092\u5b66\u3076\u3053\u3068\u306f\u3001C\u8a00\u8a9e\u306e\u5236\u5fa1\u69cb\u6587\u3092\u6df1\u304f\u7406\u89e3\u3059\u308b\u3046\u3048\u3067\u975e\u5e38\u306b\u6709\u76ca\u3067\u3059\u3002\u307e\u305f\u3001\u7d44\u307f\u8fbc\u307f\u958b\u767a\u306a\u3069\u6a19\u6e96\u30e9\u30a4\u30d6\u30e9\u30ea\u304c\u4f7f\u3048\u306a\u3044\u74b0\u5883\u3084\u3001\u30a4\u30f3\u30e9\u30a4\u30f3\u5c55\u958b\u306b\u3088\u308b\u6700\u9069\u5316\u304c\u5fc5\u8981\u306a\u5834\u9762\u3067\u3082\u5f79\u7acb\u3061\u307e\u3059\u3002\u3053\u3053\u3067\u306f3\u7a2e\u985e\u306e\u5b9f\u88c5\u65b9\u6cd5\u3092\u7d39\u4ecb\u3057\u307e\u3059\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>\u30d1\u30bf\u30fc\u30f31\uff1aif-else\u6587\u306b\u3088\u308b\u5b9f\u88c5<\/strong>\u304c\u6700\u3082\u308f\u304b\u308a\u3084\u3059\u3044\u57fa\u672c\u5b9f\u88c5\u3067\u3059\u3002\u6761\u4ef6\u5206\u5c90\u3092\u660e\u793a\u7684\u306b\u66f8\u304f\u305f\u3081\u3001\u30b3\u30fc\u30c9\u306e\u610f\u56f3\u304c\u306f\u3063\u304d\u308a\u4f1d\u308f\u308a\u307e\u3059\u3002<\/p>\n\n\n\n<pre style=\"background:#1e1e1e;color:#d4d4d4;padding:20px 24px;border-radius:8px;overflow-x:auto;line-height:1.7;margin:20px 0;font-size:14px;\"><code>#include &lt;stdio.h&gt;\n\n\/* if-else \u3067\u7d76\u5bfe\u5024\u3092\u6c42\u3081\u308b\u95a2\u6570 *\/\nint my_abs_int(int x) {\n    if (x &lt; 0) {\n        return -x;\n    } else {\n        return x;\n    }\n}\n\ndouble my_abs_double(double x) {\n    if (x &lt; 0.0) {\n        return -x;\n    } else {\n        return x;\n    }\n}\n\nint main(void) {\n    printf(\"my_abs_int(-7)    = %d\\n\",  my_abs_int(-7));     \/* 7 *\/\n    printf(\"my_abs_int(3)     = %d\\n\",  my_abs_int(3));      \/* 3 *\/\n    printf(\"my_abs_double(-2.5) = %f\\n\", my_abs_double(-2.5)); \/* 2.5 *\/\n    return 0;\n}<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>\u30d1\u30bf\u30fc\u30f32\uff1a\u4e09\u9805\u6f14\u7b97\u5b50\uff08\u6761\u4ef6\u6f14\u7b97\u5b50\uff09\u306b\u3088\u308b\u5b9f\u88c5<\/strong>\u3067\u3059\u3002if-else\u3092\u3088\u308a\u7c21\u6f54\u306b1\u884c\u3067\u66f8\u3051\u307e\u3059\u3002\u6570\u5f0f\u306e\u3088\u3046\u306b\u8aad\u3081\u308b\u305f\u3081\u3001\u6163\u308c\u305f\u958b\u767a\u8005\u306b\u306f\u597d\u307e\u308c\u308b\u66f8\u304d\u65b9\u3067\u3059\u3002<\/p>\n\n\n\n<pre style=\"background:#1e1e1e;color:#d4d4d4;padding:20px 24px;border-radius:8px;overflow-x:auto;line-height:1.7;margin:20px 0;font-size:14px;\"><code>#include &lt;stdio.h&gt;\n\n\/* \u4e09\u9805\u6f14\u7b97\u5b50\u3067\u7d76\u5bfe\u5024\u3092\u6c42\u3081\u308b *\/\nint my_abs_ternary(int x) {\n    return (x &lt; 0) ? -x : x;\n}\n\ndouble my_fabs_ternary(double x) {\n    return (x &lt; 0.0) ? -x : x;\n}\n\nint main(void) {\n    int values[] = {-5, 0, 3, -100, 42};\n    int n = sizeof(values) \/ sizeof(values[0]);\n\n    printf(\"\u4e09\u9805\u6f14\u7b97\u5b50\u306b\u3088\u308b\u7d76\u5bfe\u5024:\\n\");\n    for (int i = 0; i &lt; n; i++) {\n        printf(\"  %4d -&gt; %4d\\n\", values[i], my_abs_ternary(values[i]));\n    }\n\n    printf(\"double\u7248: %.3f\\n\", my_fabs_ternary(-3.14));  \/* 3.140 *\/\n    return 0;\n}<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>\u30d1\u30bf\u30fc\u30f33\uff1a\u30de\u30af\u30ed\uff08#define\uff09\u306b\u3088\u308b\u5b9f\u88c5<\/strong>\u3067\u3059\u3002\u95a2\u6570\u547c\u3073\u51fa\u3057\u306e\u30aa\u30fc\u30d0\u30fc\u30d8\u30c3\u30c9\u304c\u306a\u304f\u3001\u578b\u306b\u4f9d\u5b58\u3057\u306a\u3044\u6c4e\u7528\u6027\u304c\u3042\u308a\u307e\u3059\u3002\u305f\u3060\u3057\u526f\u4f5c\u7528\u306e\u3042\u308b\u5f0f\u3092\u6e21\u3059\u3068\u554f\u984c\u304c\u8d77\u304d\u308b\u305f\u3081\u3001\u4f7f\u3044\u65b9\u306b\u306f\u6ce8\u610f\u304c\u5fc5\u8981\u3067\u3059\u3002<\/p>\n\n\n\n<pre style=\"background:#1e1e1e;color:#d4d4d4;padding:20px 24px;border-radius:8px;overflow-x:auto;line-height:1.7;margin:20px 0;font-size:14px;\"><code>#include &lt;stdio.h&gt;\n\n\/* \u30de\u30af\u30ed\u306b\u3088\u308b\u7d76\u5bfe\u5024\u306e\u5b9a\u7fa9 *\/\n#define MY_ABS(x)  ((x) &lt; 0 ? -(x) : (x))\n\nint main(void) {\n    int   i = -10;\n    float f = -3.14f;\n    double d = -2.718;\n\n    \/* \u3069\u306e\u578b\u3067\u3082\u4f7f\u7528\u53ef\u80fd\uff08\u578b\u5909\u63db\u306f\u547c\u3073\u51fa\u3057\u5074\u306e\u8cac\u4efb\uff09 *\/\n    printf(\"MY_ABS(%d)   = %d\\n\",   i, MY_ABS(i));   \/* 10 *\/\n    printf(\"MY_ABS(%f)  = %f\\n\",   f, MY_ABS(f));   \/* 3.140000 *\/\n    printf(\"MY_ABS(%lf) = %lf\\n\",  d, MY_ABS(d));   \/* 2.718000 *\/\n\n    return 0;\n}<\/code><\/pre>\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\">\u4e09\u9805\u6f14\u7b97\u5b50\u7248\u306f\u7c21\u6f54\u3067\u3088\u3044\u306e\u3067\u3059\u304c\u3001\u30de\u30af\u30ed\u306f\u300c\u526f\u4f5c\u7528\u306e\u3042\u308b\u5f0f\u300d\u3092\u6e21\u3057\u305f\u3068\u304d\u306b\u610f\u56f3\u3057\u306a\u3044\u52d5\u4f5c\u306b\u306a\u308a\u307e\u3059\u3002MY_ABS(i++) \u306e\u3088\u3046\u306b\u6e21\u3059\u3068 i \u306e\u66f4\u65b0\u304c2\u56de\u5b9f\u884c\u3055\u308c\u308b\u30d0\u30b0\u304c\u751f\u3058\u307e\u3059\u3002\u30de\u30af\u30ed\u306f\u30b7\u30f3\u30d7\u30eb\u306a\u5909\u6570\u3084\u5b9a\u6570\u306b\u3060\u3051\u4f7f\u3046\u3068\u5b89\u5168\u3067\u3059\u3002<\/div>\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;\">\u30de\u30af\u30ed\u306b\u526f\u4f5c\u7528\u306e\u3042\u308b\u5f0f\u3092\u6e21\u3057\u3066\u306f\u3044\u3051\u306a\u3044<\/strong>\n  <\/div>\n  <p style=\"margin:0;font-size:15px;line-height:1.8;color:#333;\">MY_ABS(i++) \u306e\u3088\u3046\u306b\u30a4\u30f3\u30af\u30ea\u30e1\u30f3\u30c8\u6f14\u7b97\u5b50\u3092\u542b\u3080\u5f0f\u3092\u6e21\u3059\u3068\u3001\u30de\u30af\u30ed\u5c55\u958b\u5f8c\u306b <code>((i++) &lt; 0 ? -(i++) : (i++))<\/code> \u306b\u306a\u308a\u307e\u3059\u3002i \u306e\u8a55\u4fa1\u304c2\u56de\u884c\u308f\u308c\u308b\u305f\u3081\u3001\u610f\u56f3\u3057\u306a\u3044\u7d50\u679c\u306b\u306a\u308a\u307e\u3059\u3002\u3053\u306e\u554f\u984c\u3092\u907f\u3051\u308b\u306b\u306f\u3001\u30de\u30af\u30ed\u306b\u6e21\u3059\u524d\u306b\u5909\u6570\u306b\u4e00\u5ea6\u4ee3\u5165\u3059\u308b\u304b\u3001\u30a4\u30f3\u30e9\u30a4\u30f3\u95a2\u6570\uff08C99\u4ee5\u964d\uff09\u3092\u4f7f\u3044\u307e\u3057\u3087\u3046\u3002<code>static inline int my_abs(int x) { return x &lt; 0 ? -x : x; }<\/code> \u306e\u3088\u3046\u306b\u3059\u308c\u3070\u526f\u4f5c\u7528\u306e\u554f\u984c\u3092\u56de\u907f\u3067\u304d\u307e\u3059\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;\">\u30a4\u30f3\u30e9\u30a4\u30f3\u95a2\u6570\u304c\u6700\u3082\u30d0\u30e9\u30f3\u30b9\u304c\u826f\u3044<\/strong>\n  <\/div>\n  <p style=\"margin:0;font-size:15px;line-height:1.8;color:#333;\">C99\u4ee5\u964d\u3067\u306f <code>static inline<\/code> \u30ad\u30fc\u30ef\u30fc\u30c9\u3092\u4f7f\u3063\u305f\u30a4\u30f3\u30e9\u30a4\u30f3\u95a2\u6570\u3092\u5b9a\u7fa9\u3067\u304d\u307e\u3059\u3002\u30de\u30af\u30ed\u3068\u540c\u69d8\u306b\u95a2\u6570\u547c\u3073\u51fa\u3057\u306e\u30aa\u30fc\u30d0\u30fc\u30d8\u30c3\u30c9\u3092\u6291\u3048\u3064\u3064\u3001\u578b\u5b89\u5168\u6027\u3068\u526f\u4f5c\u7528\u306e\u554f\u984c\u3092\u89e3\u6c7a\u3067\u304d\u307e\u3059\u3002\u7d44\u307f\u8fbc\u307f\u7cfb\u3067\u306e\u81ea\u4f5c\u5b9f\u88c5\u306b\u304a\u3044\u3066\u306f\u3001\u30de\u30af\u30ed\u3088\u308a\u3082\u30a4\u30f3\u30e9\u30a4\u30f3\u95a2\u6570\u306e\u307b\u3046\u304c\u5b89\u5168\u3067\u63a8\u5968\u3055\u308c\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\">\u81ea\u4f5c\u5b9f\u88c5\u306fC\u8a00\u8a9e\u306e\u4ed5\u7d44\u307f\u3092\u6df1\u304f\u7406\u89e3\u3059\u308b\u305f\u3081\u306e\u826f\u3044\u7df4\u7fd2\u306b\u306a\u308a\u307e\u3059\u3002\u305f\u3060\u3057\u5b9f\u969b\u306e\u30d7\u30ed\u30b8\u30a7\u30af\u30c8\u3067\u306f\u3001\u6a19\u6e96\u30e9\u30a4\u30d6\u30e9\u30ea\u306e\u95a2\u6570\u3092\u4f7f\u3046\u307b\u3046\u304c\u30d0\u30b0\u304c\u5c11\u306a\u304f\u3001\u53ef\u8aad\u6027\u3082\u9ad8\u304f\u306a\u308a\u307e\u3059\u3002\u6a19\u6e96\u95a2\u6570\u304c\u3042\u308b\u5834\u9762\u3067\u306f\u7d20\u76f4\u306b\u4f7f\u3044\u307e\u3057\u3087\u3046\u3002<\/div>\n<\/div>\n\n\n\n<div style=\"margin:48px 0 8px;text-align:center;\">\n  <a href=\"https:\/\/aikanri.genai-ai.co.jp\/?utm_source=blog&utm_medium=article&utm_campaign=cc-c-absolute-value&utm_content=h2-banner\" target=\"_blank\" rel=\"noopener\">\n    <img decoding=\"async\" src=\"https:\/\/genai-ai.co.jp\/ai-kanri\/wp-content\/uploads\/2026\/04\/cta_blog.jpg\" alt=\"Claude Code\u3092\u7d4c\u55b6\u306b\u6d3b\u304b\u3057\u305f\u3044\u65b9\u3078 \u2014 AI\u9b3c\u7ba1\u7406\" style=\"width:100%;max-width:800px;height:auto;border-radius:8px;display:inline-block;\">\n  <\/a>\n<\/div>\n\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;\">COMMON ERRORS<\/span>\n  <span class=\"section-title\" style=\"display:block;\">\u3088\u304f\u3042\u308b\u9593\u9055\u3044\u3068\u30a8\u30e9\u30fc<\/span>\n  <span class=\"section-desc\">\u578b\u30df\u30b9\u30de\u30c3\u30c1\u30fb\u30d8\u30c3\u30c0\u5fd8\u308c\u30fb\u672a\u5b9a\u7fa9\u52d5\u4f5c\u306e\u56de\u907f\u6cd5<\/span>\n<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">C\u8a00\u8a9e\u306e\u7d76\u5bfe\u5024\u95a2\u6570\u306b\u95a2\u9023\u3057\u3066\u3088\u304f\u898b\u3089\u308c\u308b\u9593\u9055\u3044\u3068\u30a8\u30e9\u30fc\u3092\u307e\u3068\u3081\u307e\u3059\u3002\u30b3\u30f3\u30d1\u30a4\u30eb\u30a8\u30e9\u30fc\u306b\u306a\u308b\u30b1\u30fc\u30b9\u3082\u3001\u8b66\u544a\u306a\u3057\u306b\u30d0\u30b0\u304c\u751f\u3058\u308b\u30b1\u30fc\u30b9\u3082\u3001\u3069\u3061\u3089\u3082\u91cd\u8981\u3067\u3059\u3002<\/p>\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;\">\u9593\u9055\u3044\u2460\uff1afloat\/double\u306babs()\u3092\u4f7f\u3046<\/strong>\n  <\/div>\n  <p style=\"margin:0;font-size:15px;line-height:1.8;color:#333;\">abs(-3.14) \u306e\u3088\u3046\u306bfloat\/double\u5024\u3092abs()\u306b\u6e21\u3059\u3068\u3001\u6697\u9ed9\u578b\u5909\u63db\u3067int\u306b\u306a\u308a\u5c0f\u6570\u90e8\u304c\u5931\u308f\u308c\u307e\u3059\u3002\u30b3\u30f3\u30d1\u30a4\u30e9\u306b\u3088\u3063\u3066\u306f\u8b66\u544a\u3092\u51fa\u3057\u307e\u3059\u304c\u3001\u30a8\u30e9\u30fc\u306b\u306f\u306a\u308a\u307e\u305b\u3093\u3002-3.14\u306e\u7d76\u5bfe\u5024\u3068\u3057\u30663\u304c\u8fd4\u308b\u305f\u3081\u3001\u8a08\u7b97\u4e0a\u306e\u8aa4\u5dee\u304c\u767a\u751f\u3057\u307e\u3059\u3002\u6b63\u89e3\uff1afabs(-3.14) \u307e\u305f\u306f fabsf(-3.14f) \u3092\u4f7f\u3046\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;\">\u9593\u9055\u3044\u2461\uff1amath.h\u3092\u30a4\u30f3\u30af\u30eb\u30fc\u30c9\u305b\u305a\u306bfabs()\u3092\u4f7f\u3046<\/strong>\n  <\/div>\n  <p style=\"margin:0;font-size:15px;line-height:1.8;color:#333;\">math.h\u3092\u30a4\u30f3\u30af\u30eb\u30fc\u30c9\u305b\u305a\u306bfabs()\u3092\u547c\u3073\u51fa\u3059\u3068\u3001\u30b3\u30f3\u30d1\u30a4\u30e9\u306b\u3088\u3063\u3066\u306f\u300c\u6697\u9ed9\u306e\u95a2\u6570\u5ba3\u8a00\u300d\u3068\u3057\u3066\u6271\u308f\u308c\u3001\u623b\u308a\u5024\u304cint\u578b\u3068\u89e3\u91c8\u3055\u308c\u307e\u3059\u3002\u7d50\u679c\u3068\u3057\u3066\u6d6e\u52d5\u5c0f\u6570\u70b9\u6570\u3092\u6b63\u3057\u304f\u6271\u3048\u305a\u3001\u8aa4\u3063\u305f\u5024\u304c\u8fd4\u308b\u3053\u3068\u304c\u3042\u308a\u307e\u3059\u3002C99\u4ee5\u964d\u3067\u306f\u6697\u9ed9\u306e\u95a2\u6570\u5ba3\u8a00\u306f\u30b3\u30f3\u30d1\u30a4\u30eb\u30a8\u30e9\u30fc\u306b\u306a\u308b\u5834\u5408\u3082\u3042\u308a\u307e\u3059\u3002\u6b63\u89e3\uff1a\u5fc5\u305a #include <math.h> \u3092\u8a18\u8ff0\u3059\u308b\u3002<\/p>\n<\/div>\n\n\n\n<p class=\"wp-block-paragraph\">\u4ee5\u4e0b\u306e\u30b3\u30fc\u30c9\u3067\u300c\u9593\u9055\u3063\u305f\u5b9f\u88c5\u300d\u3068\u300c\u6b63\u3057\u3044\u5b9f\u88c5\u300d\u3092\u6bd4\u8f03\u3057\u3066\u307f\u307e\u3057\u3087\u3046\u3002<\/p>\n\n\n\n<pre style=\"background:#1e1e1e;color:#d4d4d4;padding:20px 24px;border-radius:8px;overflow-x:auto;line-height:1.7;margin:20px 0;font-size:14px;\"><code>#include &lt;stdio.h&gt;\n#include &lt;stdlib.h&gt;\n#include &lt;math.h&gt;\n\nint main(void) {\n    double x = -3.14;\n    float  y = -2.5f;\n\n    \/* \u9593\u9055\u3044: abs()\u3092float\/double\u306b\u4f7f\u3046 *\/\n    \/* int result_wrong = abs(x); *\/   \/* 3 \u306b\u306a\u3063\u3066\u3057\u307e\u3046\uff08\u5c0f\u6570\u90e8\u640d\u5931\uff09 *\/\n\n    \/* \u6b63\u3057\u3044: \u578b\u306b\u5408\u3063\u305f\u95a2\u6570\u3092\u4f7f\u3046 *\/\n    double result_d = fabs(x);   \/* 3.14 *\/\n    float  result_f = fabsf(y);  \/* 2.5 *\/\n\n    printf(\"fabs(%f)  = %f\\n\", x, result_d);  \/* 3.140000 *\/\n    printf(\"fabsf(%f) = %f\\n\", y, result_f);  \/* 2.500000 *\/\n\n    \/* \u9593\u9055\u3044: labs()\u306bint\u5024\u3092\u6e21\u3059\uff08\u578b\u306e\u4e0d\u4e00\u81f4\u3001\u8b66\u544a\u304c\u51fa\u308b\u5834\u5408\u3082\uff09 *\/\n    int a = -100;\n    \/* long result_wrong2 = labs(a); *\/ \/* \u52d5\u304f\u304c\u6697\u9ed9\u5909\u63db\u3042\u308a *\/\n\n    \/* \u6b63\u3057\u3044: int\u306b\u306fabs()\u3092\u4f7f\u3046 *\/\n    int result_i = abs(a);   \/* 100 *\/\n    printf(\"abs(%d) = %d\\n\", a, result_i);\n\n    return 0;\n}<\/code><\/pre>\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\u30b3\u30f3\u30d1\u30a4\u30eb\u304c\u901a\u3063\u305f\u300d\u300c\u5b9f\u884c\u6642\u306b\u30af\u30e9\u30c3\u30b7\u30e5\u3057\u306a\u3044\u300d=\u300c\u6b63\u3057\u3044\u300d\u3067\u306f\u3042\u308a\u307e\u305b\u3093\u3002\u578b\u30df\u30b9\u30de\u30c3\u30c1\u306e\u30d0\u30b0\u306f\u3001\u7279\u5b9a\u306e\u6761\u4ef6\u3067\u3057\u304b\u9855\u5728\u5316\u3057\u306a\u3044\u3053\u3068\u304c\u3042\u308a\u3001\u30c7\u30d0\u30c3\u30b0\u304c\u975e\u5e38\u306b\u56f0\u96e3\u3067\u3059\u3002\u30b3\u30fc\u30c7\u30a3\u30f3\u30b0\u6642\u70b9\u3067\u578b\u3092\u610f\u8b58\u3059\u308b\u3053\u3068\u304c\u6700\u5927\u306e\u9632\u885b\u7b56\u3067\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>abs()\u306fint\u578b\u5c02\u7528<\/strong>\uff1afloat\/double\u306b\u4f7f\u3046\u3068\u5c0f\u6570\u90e8\u304c\u5931\u308f\u308c\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>fabs()\u306fdouble\u578b\u5c02\u7528<\/strong>\uff1afloat\u578b\u306b\u306ffabsf()\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>math.h\u306e\u30a4\u30f3\u30af\u30eb\u30fc\u30c9\u5fd8\u308c<\/strong>\uff1afabs\/fabsf\u4f7f\u7528\u6642\u306f\u5fc5\u9808<\/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>-lm\u30aa\u30d7\u30b7\u30e7\u30f3<\/strong>\uff1aGCC\uff08Linux\uff09\u3067\u306f\u30b3\u30f3\u30d1\u30a4\u30eb\u6642\u306b\u5fd8\u308c\u305a\u306b\u8ffd\u52a0<\/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>INT_MIN\u306eabs()<\/strong>\uff1a-2147483648\u3092abs()\u306b\u6e21\u3059\u3068\u672a\u5b9a\u7fa9\u52d5\u4f5c\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>\u30de\u30af\u30ed\u3078\u306e\u526f\u4f5c\u7528\u5f0f\u306e\u6e21\u3057<\/strong>\uff1aMY_ABS(i++)\u306e\u3088\u3046\u306b\u66f8\u304b\u306a\u3044<\/span><\/div>\n\n<\/div>\n\n\n\n<div style=\"margin:48px 0 8px;text-align:center;\">\n  <a href=\"https:\/\/aikanri.genai-ai.co.jp\/?utm_source=blog&utm_medium=article&utm_campaign=cc-c-absolute-value&utm_content=h2-banner\" target=\"_blank\" rel=\"noopener\">\n    <img decoding=\"async\" src=\"https:\/\/genai-ai.co.jp\/ai-kanri\/wp-content\/uploads\/2026\/04\/cta_blog.jpg\" alt=\"Claude Code\u3092\u7d4c\u55b6\u306b\u6d3b\u304b\u3057\u305f\u3044\u65b9\u3078 \u2014 AI\u9b3c\u7ba1\u7406\" style=\"width:100%;max-width:800px;height:auto;border-radius:8px;display:inline-block;\">\n  <\/a>\n<\/div>\n\n\n\n<div id=\"faq\"><\/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;\">FAQ<\/span>\n  <span class=\"section-title\" style=\"display:block;\">\u3088\u304f\u3042\u308b\u8cea\u554f<\/span>\n  <span class=\"section-desc\">C\u8a00\u8a9e\u306e\u7d76\u5bfe\u5024\u306b\u3064\u3044\u3066\u3088\u304f\u5bc4\u305b\u3089\u308c\u308b\u7591\u554f\u306b\u7b54\u3048\u308b<\/span>\n<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">C\u8a00\u8a9e\u306e\u7d76\u5bfe\u5024\u95a2\u6570\u306b\u3064\u3044\u3066\u3088\u304f\u5bc4\u305b\u3089\u308c\u308b\u8cea\u554f\u3092\u307e\u3068\u3081\u307e\u3059\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Q1. abs()\u3068fabs()\u306e\u9055\u3044\u306f\u4f55\u3067\u3059\u304b\uff1f<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">A. <strong>\u6271\u3046\u30c7\u30fc\u30bf\u578b\u304c\u7570\u306a\u308a\u307e\u3059<\/strong>\u3002abs()\u306fint\u578b\uff08\u6574\u6570\uff09\u7528\u3001fabs()\u306fdouble\u578b\uff08\u6d6e\u52d5\u5c0f\u6570\u70b9\u6570\uff09\u7528\u306e\u7d76\u5bfe\u5024\u95a2\u6570\u3067\u3059\u3002abs()\u306b\u6d6e\u52d5\u5c0f\u6570\u70b9\u6570\u3092\u6e21\u3059\u3068\u5c0f\u6570\u90e8\u304c\u5207\u308a\u6368\u3066\u3089\u308c\u3066\u3057\u307e\u3044\u307e\u3059\u3002\u4f7f\u7528\u3059\u308b\u30d8\u30c3\u30c0\u30d5\u30a1\u30a4\u30eb\u3082\u7570\u306a\u308a\u3001abs()\u306f<code>&lt;stdlib.h&gt;<\/code>\u3001fabs()\u306f<code>&lt;math.h&gt;<\/code>\u3067\u3059\u3002\u5909\u6570\u306e\u578b\u3092\u78ba\u8a8d\u3057\u3066\u6b63\u3057\u3044\u95a2\u6570\u3092\u9078\u3076\u3053\u3068\u304c\u91cd\u8981\u3067\u3059\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Q2. fabs\u3068fabsf\u306e\u3069\u3061\u3089\u3092\u4f7f\u3048\u3070\u3088\u3044\u3067\u3059\u304b\uff1f<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">A. <strong>\u5909\u6570\u306e\u578b\u306b\u5408\u308f\u305b\u3066\u9078\u3073\u307e\u3059<\/strong>\u3002double\u578b\u306e\u5909\u6570\u306b\u306ffabs()\u3001float\u578b\u306e\u5909\u6570\u306b\u306ffabsf()\u3092\u4f7f\u3044\u307e\u3059\u3002float\u578b\u306e\u5909\u6570\u306bfabs()\u3092\u4f7f\u3046\u3068\u3001\u5f15\u6570\u304cdouble\u306b\u6607\u683c\u3057\u3066\u8a08\u7b97\u3055\u308c\u3001\u305d\u306e\u5f8cfloat\u306b\u623b\u3055\u308c\u308b\u305f\u3081\u3001\u51e6\u7406\u306f\u6b63\u3057\u304f\u884c\u308f\u308c\u307e\u3059\u304c\u3001\u578b\u5909\u63db\u306e\u30aa\u30fc\u30d0\u30fc\u30d8\u30c3\u30c9\u304c\u767a\u751f\u3057\u307e\u3059\u3002\u53b3\u5bc6\u306afloat\u578b\u306e\u8a08\u7b97\u304c\u5fc5\u8981\u306a\u7d44\u307f\u8fbc\u307f\u74b0\u5883\u3067\u306ffabsf()\u3092\u660e\u793a\u7684\u306b\u4f7f\u3046\u3053\u3068\u3092\u63a8\u5968\u3057\u307e\u3059\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Q3. math.h\u3092\u30a4\u30f3\u30af\u30eb\u30fc\u30c9\u3057\u306a\u304f\u3066\u3082fabs\u304c\u52d5\u304f\u3053\u3068\u304c\u3042\u308a\u307e\u3059\u304c\u3001\u306a\u305c\u3067\u3059\u304b\uff1f<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">A. \u30b3\u30f3\u30d1\u30a4\u30e9\u3084\u74b0\u5883\u306b\u3088\u3063\u3066\u306f\u3001\u4ed6\u306e\u30d8\u30c3\u30c0\u30d5\u30a1\u30a4\u30eb\u304c\u9593\u63a5\u7684\u306bmath.h\u306e\u5185\u5bb9\u3092\u53d6\u308a\u8fbc\u3080\u3053\u3068\u304c\u3042\u308a\u307e\u3059\u3002\u307e\u305f\u3001\u53e4\u3044C\u898f\u683c\uff08C89\u4ee5\u524d\uff09\u3067\u306f\u6697\u9ed9\u306e\u95a2\u6570\u5ba3\u8a00\u304c\u8a31\u53ef\u3055\u308c\u3066\u3044\u305f\u305f\u3081\u3001\u30a4\u30f3\u30af\u30eb\u30fc\u30c9\u306a\u3057\u3067\u52d5\u3044\u3066\u3057\u307e\u3046\u30b1\u30fc\u30b9\u304c\u3042\u308a\u307e\u3057\u305f\u3002\u3057\u304b\u3057<strong>\u3053\u308c\u306f\u79fb\u690d\u6027\u306e\u306a\u3044\u5076\u7136\u306e\u52d5\u4f5c<\/strong>\u3067\u3059\u3002C99\u4ee5\u964d\u3067\u306f\u6697\u9ed9\u306e\u5ba3\u8a00\u306f\u30a8\u30e9\u30fc\u307e\u305f\u306f\u8b66\u544a\u306b\u306a\u308a\u307e\u3059\u3002\u5fc5\u305a\u660e\u793a\u7684\u306b#include &lt;math.h&gt;\u3092\u8a18\u8ff0\u3057\u3066\u304f\u3060\u3055\u3044\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Q4. C++\u3067C\u8a00\u8a9e\u306e\u7d76\u5bfe\u5024\u95a2\u6570\u3092\u4f7f\u3048\u307e\u3059\u304b\uff1f<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">A. C++\u3067\u306f<code>&lt;cstdlib&gt;<\/code>\u30fb<code>&lt;cmath&gt;<\/code>\u3092\u30a4\u30f3\u30af\u30eb\u30fc\u30c9\u3059\u308b\u3053\u3068\u3067\u540c\u69d8\u306e\u95a2\u6570\u304c\u4f7f\u3048\u307e\u3059\u3002\u3055\u3089\u306bC++\u3067\u306f<code>std::abs<\/code>\u304c\u30aa\u30fc\u30d0\u30fc\u30ed\u30fc\u30c9\u3055\u308c\u3066\u304a\u308a\u3001int\/long\/long long\/float\/double\/long double\u306e\u3059\u3079\u3066\u306b\u5bfe\u3057\u3066\u6b63\u3057\u304f\u52d5\u4f5c\u3057\u307e\u3059\u3002C++\u3092\u4f7f\u3046\u5834\u5408\u306f<code>#include &lt;cmath&gt;<\/code>\u3068<code>std::abs(x)<\/code>\u3092\u4f7f\u3046\u3068\u578b\u306b\u5fdc\u3058\u3066\u81ea\u52d5\u9078\u629e\u3055\u308c\u308b\u305f\u3081\u4fbf\u5229\u3067\u3059\u3002C\u8a00\u8a9e\u3067\u306e\u660e\u793a\u7684\u306a\u578b\u5225\u95a2\u6570\u9078\u629e\u306f\u4e0d\u8981\u306b\u306a\u308a\u307e\u3059\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Q5. -lm\u30aa\u30d7\u30b7\u30e7\u30f3\u3068\u306f\u4f55\u3067\u3059\u304b\uff1f\u3069\u3093\u306a\u74b0\u5883\u3067\u5fc5\u8981\u3067\u3059\u304b\uff1f<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">A. <code>-lm<\/code>\u306fGCC\u3067\u30b3\u30f3\u30d1\u30a4\u30eb\u3059\u308b\u969b\u306b\u6570\u5b66\u30e9\u30a4\u30d6\u30e9\u30ea\uff08libm\uff09\u3092\u30ea\u30f3\u30af\u3059\u308b\u30aa\u30d7\u30b7\u30e7\u30f3\u3067\u3059\u3002Linux\u3084macOS\u4e0a\u3067GCC\u3092\u4f7f\u3063\u3066fabs()\u306a\u3069\u306emath.h\u95a2\u6570\u3092\u542b\u3080\u30d7\u30ed\u30b0\u30e9\u30e0\u3092\u30b3\u30f3\u30d1\u30a4\u30eb\u3059\u308b\u3068\u304d\u306b\u5fc5\u8981\u3067\u3059\uff08\u4f8b\uff1a<code>gcc myfile.c -o myfile -lm<\/code>\uff09\u3002\u4e00\u65b9\u3001Windows\u4e0a\u306eMinGW\u3084Visual Studio\u3067\u306flibm\u304c\u30c7\u30d5\u30a9\u30eb\u30c8\u3067\u30ea\u30f3\u30af\u3055\u308c\u308b\u305f\u3081\u3001-lm\u30aa\u30d7\u30b7\u30e7\u30f3\u304c\u4e0d\u8981\u306a\u3053\u3068\u304c\u307b\u3068\u3093\u3069\u3067\u3059\u3002\u300cundefined reference to `fabs'\u300d\u3068\u3044\u3046\u30a8\u30e9\u30fc\u304c\u51fa\u305f\u3089\u3001-lm\u306e\u8ffd\u52a0\u3067\u89e3\u6c7a\u3057\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\">FAQ\u3092\u3072\u3068\u901a\u308a\u8aad\u3093\u3067\u300c\u308f\u304b\u3063\u305f\u300d\u3068\u601d\u3063\u3066\u3082\u3001\u5b9f\u969b\u306b\u81ea\u5206\u3067\u30b3\u30fc\u30c9\u3092\u66f8\u3044\u3066\u52d5\u304b\u3057\u3066\u307f\u308b\u3053\u3068\u304c\u7406\u89e3\u306e\u5b9a\u7740\u306b\u4e0d\u53ef\u6b20\u3067\u3059\u3002\u3053\u306e\u8a18\u4e8b\u306e\u30b5\u30f3\u30d7\u30eb\u30b3\u30fc\u30c9\u3092\u30b3\u30d4\u30fc\u3057\u3066\u5b9f\u884c\u3057\u3066\u307f\u3066\u304f\u3060\u3055\u3044\u3002<\/div>\n<\/div>\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\": \"abs()\u3068fabs()\u306e\u9055\u3044\u306f\u4f55\u3067\u3059\u304b\uff1f\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"abs()\u306fint\u578b\uff08\u6574\u6570\uff09\u306e\u7d76\u5bfe\u5024\u3092\u6c42\u3081\u308b\u95a2\u6570\u3067stdlib.h\u304c\u5fc5\u8981\u3001fabs()\u306fdouble\u578b\uff08\u6d6e\u52d5\u5c0f\u6570\u70b9\u6570\uff09\u306e\u7d76\u5bfe\u5024\u3092\u6c42\u3081\u308b\u95a2\u6570\u3067math.h\u304c\u5fc5\u8981\u3067\u3059\u3002abs()\u306bfloat\/double\u3092\u6e21\u3059\u3068\u5c0f\u6570\u90e8\u304c\u5931\u308f\u308c\u308b\u305f\u3081\u3001\u578b\u306b\u5fdc\u3058\u305f\u95a2\u6570\u3092\u4f7f\u3044\u5206\u3051\u308b\u3053\u3068\u304c\u91cd\u8981\u3067\u3059\u3002\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"C\u8a00\u8a9e\u3067float\u578b\u306e\u7d76\u5bfe\u5024\u3092\u6c42\u3081\u308b\u306b\u306f\u3069\u3046\u3059\u308c\u3070\u3088\u3044\u3067\u3059\u304b\uff1f\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"float\u578b\u306e\u7d76\u5bfe\u5024\u306b\u306ffabsf()\u3092\u4f7f\u3044\u307e\u3059\u3002#include <math.h>\u3092\u30a4\u30f3\u30af\u30eb\u30fc\u30c9\u3057\u3066\u3001fabsf(x)\u306e\u3088\u3046\u306b\u547c\u3073\u51fa\u3057\u3066\u304f\u3060\u3055\u3044\u3002double\u578b\u306e\u5834\u5408\u306ffabs()\u3092\u4f7f\u3044\u307e\u3059\u3002GCC\uff08Linux\uff09\u74b0\u5883\u3067\u306f\u30b3\u30f3\u30d1\u30a4\u30eb\u6642\u306b-lm\u30aa\u30d7\u30b7\u30e7\u30f3\u304c\u5fc5\u8981\u306a\u5834\u5408\u304c\u3042\u308a\u307e\u3059\u3002\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"C\u8a00\u8a9e\u3067long long\u578b\u306e\u7d76\u5bfe\u5024\u3092\u6c42\u3081\u308b\u306b\u306f\u3069\u3046\u3059\u308c\u3070\u3088\u3044\u3067\u3059\u304b\uff1f\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"long long\u578b\u306e\u7d76\u5bfe\u5024\u306b\u306fllabs()\u3092\u4f7f\u3044\u307e\u3059\u3002#include <stdlib.h>\u3092\u30a4\u30f3\u30af\u30eb\u30fc\u30c9\u3057\u3066\u3001llabs(x)\u306e\u3088\u3046\u306b\u547c\u3073\u51fa\u3057\u3066\u304f\u3060\u3055\u3044\u3002C99\u4ee5\u964d\u3067\u4f7f\u7528\u53ef\u80fd\u3067\u3059\u3002long\u578b\u306b\u306flabs()\u3001int\u578b\u306b\u306fabs()\u3092\u4f7f\u3044\u307e\u3059\u3002\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"fabs()\u3067\u30a8\u30e9\u30fc\u300cundefined reference to fabs\u300d\u304c\u51fa\u307e\u3059\u3002\u89e3\u6c7a\u65b9\u6cd5\u306f\uff1f\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"GCC\uff08Linux\/macOS\uff09\u74b0\u5883\u3067\u306e\u30ea\u30f3\u30af\u30a8\u30e9\u30fc\u3067\u3059\u3002\u30b3\u30f3\u30d1\u30a4\u30eb\u6642\u306b -lm \u30aa\u30d7\u30b7\u30e7\u30f3\u3092\u8ffd\u52a0\u3057\u3066\u304f\u3060\u3055\u3044\u3002\u4f8b\uff1agcc myfile.c -o myfile -lm\u3002\u307e\u305f\u3001#include <math.h>\u304c\u8a18\u8ff0\u3055\u308c\u3066\u3044\u308b\u304b\u3082\u78ba\u8a8d\u3057\u3066\u304f\u3060\u3055\u3044\u3002Windows\u306e\u30b3\u30f3\u30d1\u30a4\u30e9\uff08MinGW\u3001Visual Studio\uff09\u3067\u306f\u3053\u306e\u30aa\u30d7\u30b7\u30e7\u30f3\u306f\u901a\u5e38\u4e0d\u8981\u3067\u3059\u3002\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"math.h\u3092\u30a4\u30f3\u30af\u30eb\u30fc\u30c9\u3057\u306a\u304f\u3066\u3082fabs\u304c\u52d5\u304f\u306e\u306f\u306a\u305c\u3067\u3059\u304b\uff1f\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"\u4ed6\u306e\u30d8\u30c3\u30c0\u304c\u9593\u63a5\u7684\u306bmath.h\u306e\u5185\u5bb9\u3092\u53d6\u308a\u8fbc\u3080\u5834\u5408\u3084\u3001\u53e4\u3044C\u898f\u683c\u306e\u6697\u9ed9\u5ba3\u8a00\u306e\u6319\u52d5\u306b\u3088\u308b\u3082\u306e\u3067\u3059\u3002\u305f\u3060\u3057\u3053\u308c\u306f\u79fb\u690d\u6027\u306e\u306a\u3044\u5076\u7136\u306e\u52d5\u4f5c\u3067\u3059\u3002C99\u4ee5\u964d\u3067\u306f\u6697\u9ed9\u306e\u95a2\u6570\u5ba3\u8a00\u306f\u30a8\u30e9\u30fc\u307e\u305f\u306f\u8b66\u544a\u306b\u306a\u308a\u307e\u3059\u3002\u5fc5\u305a\u660e\u793a\u7684\u306b#include <math.h>\u3092\u8a18\u8ff0\u3057\u3066\u304f\u3060\u3055\u3044\u3002\"\n      }\n    }\n  ]\n}\n<\/script>\n\n\n\n<div style=\"margin:48px 0 8px;text-align:center;\">\n  <a href=\"https:\/\/aikanri.genai-ai.co.jp\/?utm_source=blog&utm_medium=article&utm_campaign=cc-c-absolute-value&utm_content=h2-banner\" target=\"_blank\" rel=\"noopener\">\n    <img decoding=\"async\" src=\"https:\/\/genai-ai.co.jp\/ai-kanri\/wp-content\/uploads\/2026\/04\/cta_blog.jpg\" alt=\"Claude Code\u3092\u7d4c\u55b6\u306b\u6d3b\u304b\u3057\u305f\u3044\u65b9\u3078 \u2014 AI\u9b3c\u7ba1\u7406\" style=\"width:100%;max-width:800px;height:auto;border-radius:8px;display:inline-block;\">\n  <\/a>\n<\/div>\n\n\n\n<div id=\"sec-summary\"><\/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;\">SUMMARY<\/span>\n  <span class=\"section-title\" style=\"display:block;\">\u307e\u3068\u3081 \u2014 C\u8a00\u8a9e\u306e\u7d76\u5bfe\u5024\u95a2\u6570\u3092\u5b8c\u5168\u30de\u30b9\u30bf\u30fc<\/span>\n  <span class=\"section-desc\">\u578b\u3092\u898b\u3066\u5373\u5ea7\u306b\u6b63\u3057\u3044\u95a2\u6570\u3092\u9078\u3079\u308b\u3088\u3046\u306b\u306a\u308d\u3046<\/span>\n<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u3053\u306e\u8a18\u4e8b\u3067\u306f\u3001C\u8a00\u8a9e\u3067\u7d76\u5bfe\u5024\u3092\u6c42\u3081\u308b\u305f\u3081\u306e\u5168\u95a2\u6570\u3092\u5fb9\u5e95\u89e3\u8aac\u3057\u307e\u3057\u305f\u3002abs\u30fblabs\u30fbllabs\u30fbfabs\u30fbfabsf\u306e5\u95a2\u6570\u306f\u3001\u305d\u308c\u305e\u308c\u6271\u3046\u30c7\u30fc\u30bf\u578b\u304c\u7570\u306a\u308a\u307e\u3059\u3002\u578b\u306b\u5408\u3063\u305f\u95a2\u6570\u3092\u4f7f\u3046\u3053\u3068\u304c\u30d0\u30b0\u306e\u306a\u3044C\u8a00\u8a9e\u30d7\u30ed\u30b0\u30e9\u30e0\u3092\u66f8\u304f\u305f\u3081\u306e\u57fa\u672c\u3067\u3059\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><strong>abs()<\/strong>\uff1aint\u578b\u5c02\u7528\u3002stdlib.h\u3092\u30a4\u30f3\u30af\u30eb\u30fc\u30c9\u3002\u6700\u3082\u57fa\u672c\u7684\u306a\u7d76\u5bfe\u5024\u95a2\u6570<\/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>labs()<\/strong>\uff1along\u578b\u5c02\u7528\u3002stdlib.h\u3092\u30a4\u30f3\u30af\u30eb\u30fc\u30c9\u3002\u74b0\u5883\u306b\u3088\u308aint\u3068\u540c\u30b5\u30a4\u30ba\u306e\u3053\u3068\u3082<\/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>llabs()<\/strong>\uff1along long\u578b\u5c02\u7528\u3002stdlib.h\u3092\u30a4\u30f3\u30af\u30eb\u30fc\u30c9\u3002C99\u4ee5\u964d\u3067\u5229\u7528\u53ef\u80fd<\/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>fabs()<\/strong>\uff1adouble\u578b\u5c02\u7528\u3002math.h\u3092\u30a4\u30f3\u30af\u30eb\u30fc\u30c9\u3002\u5c0f\u6570\u306e\u7d76\u5bfe\u5024\u306e\u6a19\u6e96\u95a2\u6570<\/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>fabsf()<\/strong>\uff1afloat\u578b\u5c02\u7528\u3002math.h\u3092\u30a4\u30f3\u30af\u30eb\u30fc\u30c9\u3002\u7d44\u307f\u8fbc\u307f\u7cfb\u3067\u591a\u7528\u3055\u308c\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>\u81ea\u4f5c\u5b9f\u88c5<\/strong>\uff1aif-else\u30fb\u4e09\u9805\u6f14\u7b97\u5b50\u30fb\u30a4\u30f3\u30e9\u30a4\u30f3\u95a2\u6570\u30fb\u30de\u30af\u30ed\u306e4\u30d1\u30bf\u30fc\u30f3\u3092\u7406\u89e3<\/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\u30df\u30b9<\/strong>\uff1a\u578b\u30df\u30b9\u30de\u30c3\u30c1\u3001\u30d8\u30c3\u30c0\u30a4\u30f3\u30af\u30eb\u30fc\u30c9\u5fd8\u308c\u3001-lm\u30aa\u30d7\u30b7\u30e7\u30f3\u5fd8\u308c<\/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\u7d76\u5bfe\u5024\u95a2\u6570\u306f\u5358\u7d14\u306b\u898b\u3048\u307e\u3059\u304c\u3001\u578b\u306e\u6982\u5ff5\u304c\u6839\u5e95\u306b\u3042\u308a\u307e\u3059\u3002\u300c\u578b\u3092\u610f\u8b58\u3057\u3066\u30b3\u30fc\u30c9\u3092\u66f8\u304f\u300d\u3068\u3044\u3046\u7fd2\u6163\u304c\u3064\u3044\u3066\u3044\u308c\u3070\u3001\u7d76\u5bfe\u5024\u306b\u9650\u3089\u305aC\u8a00\u8a9e\u5168\u822c\u306e\u30d0\u30b0\u3092\u5927\u5e45\u306b\u6e1b\u3089\u305b\u307e\u3059\u3002\u3053\u306e\u8a18\u4e8b\u304c\u578b\u3078\u306e\u610f\u8b58\u3092\u9ad8\u3081\u308b\u304d\u3063\u304b\u3051\u306b\u306a\u308c\u3070\u5e78\u3044\u3067\u3059\u3002<\/div>\n<\/div>\n\n\n\n<p style=\"font-size:15px;line-height:1.8;color:#333;margin:0 0 12px;\">\nC\u8a00\u8a9e\u3092\u542b\u3080\u30d7\u30ed\u30b0\u30e9\u30df\u30f3\u30b0\u306e\u30b9\u30ad\u30eb\u3092\u696d\u52d9\u52b9\u7387\u5316\u306b\u3064\u306a\u3052\u305f\u3044\u65b9\u3001AI\u3092\u6d3b\u7528\u3057\u3066\u958b\u767a\u751f\u7523\u6027\u3092\u4e0a\u3052\u305f\u3044\u65b9\u306f\u3001<strong>AI\u9b3c\u7ba1\u7406\u306e\u7121\u6599\u76f8\u8ac7<\/strong>\u3092\u304a\u6c17\u8efd\u306b\u3054\u5229\u7528\u304f\u3060\u3055\u3044\u3002\n<\/p>\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-absolute-value&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","protected":false},"excerpt":{"rendered":"<p>C\u8a00\u8a9e\u3067\u7d76\u5bfe\u5024\u3092\u6c42\u3081\u308babs\u30fblabs\u30fbfabs\u30fbfabsf\u95a2\u6570\u306e\u4f7f\u3044\u5206\u3051\u3092\u5b8c\u5168\u89e3\u8aac\u3002\u30c7\u30fc\u30bf\u578b\u3054\u3068\u306e\u6b63\u3057\u3044\u95a2\u6570\u9078\u629e\u3001stdlib.h\u3068math.h\u306e\u30a4\u30f3\u30af\u30eb\u30fc\u30c9\u65b9\u6cd5\u3001if-else\u30fb\u4e09\u9805\u6f14\u7b97\u5b50\u306b\u3088\u308b\u81ea\u4f5c\u5b9f\u88c5\u307e\u3067\u3001\u30b3\u30fc\u30c9\u4f8b\u4ed8\u304d\u3067\u5fb9\u5e95\u89e3\u8aac\u3002<\/p>\n","protected":false},"author":1,"featured_media":18382,"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\u3067\u7d76\u5bfe\u5024\u3092\u6c42\u3081\u308babs\u30fblabs\u30fbfabs\u30fbfabsf\u95a2\u6570\u306e\u4f7f\u3044\u5206\u3051\u3092\u5b8c\u5168\u89e3\u8aac\u3002\u30c7\u30fc\u30bf\u578b\u3054\u3068\u306e\u6b63\u3057\u3044\u95a2\u6570\u9078\u629e\u3001stdlib.h\u3068math.h\u306e\u30a4\u30f3\u30af\u30eb\u30fc\u30c9\u65b9\u6cd5\u3001if-else\u30fb\u4e09\u9805\u6f14\u7b97\u5b50\u306b\u3088\u308b\u81ea\u4f5c\u5b9f\u88c5\u307e\u3067\u3001\u30b3\u30fc\u30c9\u4f8b\u4ed8\u304d\u3067\u5fb9\u5e95\u89e3\u8aac\u3002","rank_math_focus_keyword":"C\u8a00\u8a9e \u7d76\u5bfe\u5024","rank_math_title":"\u30102026\u5e747\u6708\u6700\u65b0\u3011C\u8a00\u8a9e\u3067\u7d76\u5bfe\u5024\u3092\u6c42\u3081\u308b\u65b9\u6cd5\u5b8c\u5168\u30ac\u30a4\u30c9\uff5cabs\u30fblabs\u30fbfabs\u30fbfabsf\u95a2\u6570\u306e\u4f7f\u3044\u5206\u3051\u3068\u5b9f\u8df5\u30b3\u30fc\u30c9\u4f8b","pending_rewrite_html":"","pending_rewrite_id":"","pending_rewrite_kw":"","pending_rewrite_at":"","pending_rewrite_source":"","pending_rewrite_brief":"","pending_rewrite_evidence":"","approved_rewrite_html":"","approved_rewrite_id":"","approved_rewrite_kw":"","approved_rewrite_at":"","approved_rewrite_by":"","approved_rewrite_brief":"","approved_rewrite_evidence":"","rewrite_tracker_baseline":"","rewrite_tracker_7day":"","rewrite_tracker_14day":"","rewrite_tracker_30day":"","rewrite_tracker_notified":""},"categories":[2],"tags":[],"class_list":["post-18383","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-claude-tips"],"_links":{"self":[{"href":"https:\/\/genai-ai.co.jp\/ai-kanri\/wp-json\/wp\/v2\/posts\/18383","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/genai-ai.co.jp\/ai-kanri\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/genai-ai.co.jp\/ai-kanri\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/genai-ai.co.jp\/ai-kanri\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/genai-ai.co.jp\/ai-kanri\/wp-json\/wp\/v2\/comments?post=18383"}],"version-history":[{"count":1,"href":"https:\/\/genai-ai.co.jp\/ai-kanri\/wp-json\/wp\/v2\/posts\/18383\/revisions"}],"predecessor-version":[{"id":18384,"href":"https:\/\/genai-ai.co.jp\/ai-kanri\/wp-json\/wp\/v2\/posts\/18383\/revisions\/18384"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/genai-ai.co.jp\/ai-kanri\/wp-json\/wp\/v2\/media\/18382"}],"wp:attachment":[{"href":"https:\/\/genai-ai.co.jp\/ai-kanri\/wp-json\/wp\/v2\/media?parent=18383"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/genai-ai.co.jp\/ai-kanri\/wp-json\/wp\/v2\/categories?post=18383"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/genai-ai.co.jp\/ai-kanri\/wp-json\/wp\/v2\/tags?post=18383"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}