{"id":2514,"date":"2025-02-18T16:59:46","date_gmt":"2025-02-18T08:59:46","guid":{"rendered":"https:\/\/guapicoding.com\/?p=2514"},"modified":"2025-09-18T10:30:35","modified_gmt":"2025-09-18T02:30:35","slug":"c%e6%b7%b1%e5%b1%82%e5%89%96%e6%9e%90","status":"publish","type":"post","link":"https:\/\/guapicoding.com\/?p=2514","title":{"rendered":"C++\u6df1\u5c42\u5256\u6790"},"content":{"rendered":"\n<h1 class=\"wp-block-heading\">\u9762\u5411\u5bf9\u8c61<\/h1>\n\n\n\n<h2 class=\"wp-block-heading\">\u591a\u6001\u7684\u5e95\u5c42\u5b9e\u73b0<\/h2>\n\n\n\n<p><strong>\u591a\u6001\u7684\u5b9e\u73b0\u5206\u4e3a\u9759\u6001\u591a\u6001\u548c\u52a8\u6001\u591a\u6001\uff1a<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u9759\u6001\u591a\u6001\uff08\u7f16\u8bd1<strong>\u65f6<\/strong>\u591a\u6001\uff09\uff1a<\/strong>\u901a\u8fc7<strong>\u51fd\u6570\u91cd\u8f7d\uff08overload\uff09\u3001\u6a21\u677f\uff08templates\uff09\u548c\u8fd0\u7b97\u7b26\u91cd\u8f7d<\/strong>\u6765\u5b9e\u73b0\uff0c<strong>\u5b83\u7684\u8c03\u7528\u5728\u7f16\u8bd1\u65f6\u5c31\u5df2\u7ecf\u786e\u5b9a<\/strong>\u3002<\/li>\n\n\n\n<li><strong>\u52a8\u6001\u591a\u6001\uff08\u8fd0\u884c\u65f6\u591a\u6001\uff09\uff1a<\/strong>\u901a\u8fc7<strong>\u7ee7\u627f\u3001\u51fd\u6570\u91cd\u5199\uff08override\uff09<\/strong>\u548c<strong>\u865a\u51fd\u6570<\/strong>\uff0c\u4f9d\u8d56<strong>\u865a\u51fd\u6570\u8868<strong>\uff08<strong>vtable<\/strong>\uff09<\/strong><\/strong>\u548c<strong>\u865a\u51fd\u6570\u8868\u6307\u9488<strong>\uff08<strong>vptr<\/strong>\uff09<\/strong><\/strong>\u5b9e\u73b0<strong>\u52a8\u6001\u7ed1\u5b9a<\/strong>\u3002<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">\u90a3\u4e48\u865a\u51fd\u6570\u7684\u5e95\u5c42\u662f\u5982\u4f55\u5b9e\u73b0\u7684\uff1f<\/h3>\n\n\n\n<p>\u6bcf\u4e2a\u5305\u542b<strong>\u865a\u51fd\u6570\u7684\u7c7b<\/strong>\u90fd\u6709\u4e00\u4e2a<strong>\u865a\u51fd\u6570\u8868<\/strong>\uff08\u5728\u7f16\u8bd1\u671f\u751f\u6210\uff0c\u5b58\u50a8\u5728\u7a0b\u5e8f\u7684\u53ea\u8bfb\u6570\u636e\u6bb5\uff09\uff0c\u5b58\u50a8\u7c7b\u7684\u6240\u6709\u865a\u51fd\u6570\u7684\u6307\u9488\uff08\u5b58\u7684\u662f\u865a\u51fd\u6570\u771f\u6b63\u7684\u5730\u5740\uff09\u3002\u6bcf\u4e2a\u5bf9\u8c61\u90fd\u6709\u4e00\u4e2a<strong>\u865a\u51fd\u6570<strong>\u8868<\/strong>\u6307\u9488<\/strong>\uff08\u4f4d\u4e8e\u5bf9\u8c61\u5185\u5b58\u7684\u9996\u90e8\uff09\uff0c\u6307\u5411\u8be5\u5bf9\u8c61\u6240\u5c5e\u7684<strong>\u865a\u51fd\u6570\u8868<\/strong>\u3002\u5f53\u8c03\u7528<strong>\u865a\u51fd\u6570<\/strong>\u65f6\uff0c\u7a0b\u5e8f\u4f1a\u901a\u8fc7<strong><strong>\u865a\u51fd\u6570<strong>\u8868<\/strong>\u6307\u9488<\/strong>\u8bbf\u95ee<strong>\u865a\u51fd\u6570\u8868<\/strong>\u627e\u5230\u771f\u6b63\u7684\u51fd\u6570\u5730\u5740<\/strong>\uff0c\u7136\u540e\u8c03\u7528\u8be5\u51fd\u6570\u3002<\/p>\n\n\n\n<p>ps\uff1a\u5728\u6784\u9020\u6d3e\u751f\u7c7b\uff08\u5b50\u7c7b\uff09\u5bf9\u8c61\u65f6\uff0c\u4f1a<strong>\u5148\u6784\u9020\u57fa\u7c7b\uff08\u7236\u7c7b\uff09<\/strong>\u90e8\u5206\uff0c\u7136\u540e<strong>\u518d\u6784\u9020\u6d3e\u751f\u7c7b<\/strong>\u81ea\u5df1\u7684\u6210\u5458\uff1b\u6790\u6784\u65f6\u6b63\u597d\u76f8\u53cd\uff0c<strong>\u5148\u9500\u6bc1\u5b50\u7c7b\uff0c\u518d\u9500\u6bc1\u57fa\u7c7b<\/strong>\uff0c\u5426\u5219\u4f1a\u51fa\u73b0\u201c\u8bbf\u95ee\u5df2\u9500\u6bc1\u5185\u5bb9\u201d\u7684\u95ee\u9898\u3002<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">\u865a\u6790\u6784\u51fd\u6570\u7684\u4f5c\u7528<\/h2>\n\n\n\n<p>\u865a\u6790\u6784\u51fd\u6570\u662f\u2f00\u4e2a\u5e26\u6709 <strong>virtual<\/strong> \u5173\u952e\u5b57\u7684\u6790\u6784\u51fd\u6570\uff0c\u4e3b\u8981\u4f5c\u7528\u662f\u786e\u4fdd\u5728\u901a\u8fc7\u57fa\u7c7b\u6307\u9488\u5220\u9664\u6d3e\u751f\u7c7b\u5bf9\u8c61\u65f6\uff0c\u80fd\u591f\u6b63\u786e\u8c03\u7528\u6d3e\u751f\u7c7b\u7684\u6790\u6784\u51fd\u6570\uff0c\u4ece\u800c\u91ca\u653e\u5bf9\u8c61\u6240\u5360\u7528\u7684\u8d44\u6e90\u3002<br>\u5373\u865a\u6790\u6784\u51fd\u6570\u5141\u8bb8\u5728\u8fd0\u2f8f\u65f6\u6839\u636e\u5bf9\u8c61\u7684\u5b9e\u9645\u7c7b\u578b\u8c03\u2f64\u6b63\u786e\u7684\u6790\u6784\u51fd\u6570\uff0c\u4ece\u800c\u5b9e\u73b0\u591a\u6001\u6027\u3002<br><strong>\u5982\u679c\u57fa\u7c7b\u7684\u6790\u6784\u51fd\u6570\u4e0d\u662f\u865a\u7684\uff0c\u5f53\u901a\u8fc7\u57fa\u7c7b\u6307\u9488\u5220\u9664\u6d3e\u751f\u7c7b\u5bf9\u8c61\u65f6\uff0c\u4e0d\u4f1a\u89e6\u53d1\u52a8\u6001\u7ed1\u5b9a\uff0c\u53ea\u4f1a\u8c03\u7528\u57fa\u7c7b\u7684\u6790\u6784\u51fd\u6570\uff0c\u800c\u4e0d\u4f1a\u8c03<strong>\u7528<\/strong>\u6d3e<strong>\u751f<\/strong>\u7c7b\u7684\u6790\u6784\u51fd\u6570\uff0c\u8fd9\u53ef\u80fd\u5bfc\u81f4\u6d3e<strong>\u751f<\/strong>\u7c7b\u7684\u8d44\u6e90\u672a\u88ab\u6b63\u786e\u91ca\u653e\uff0c\u9020\u6210\u5185\u5b58\u6cc4\u6f0f\u3002<\/strong><\/p>\n\n\n\n<p>PS\uff1a<strong>\u5185\u5b58\u6cc4\u6f0f\u6307\u7a0b\u5e8f\u672a\u80fd\u91ca\u653e\u6389\u4e0d\u518d\u4f7f\u7528\u7684\u5185\u5b58\u7684\u60c5\u51b5<\/strong><\/p>\n\n\n\n<h3 class=\"wp-block-heading\"> <br> \u90a3\u4e3a\u4ec0\u4e48\u6ca1\u6709\u865a\u6784\u9020\u51fd\u6570\uff1f<\/h3>\n\n\n\n<p>\u865a\u51fd\u6570\u8868\u662f\u7c7b\u7ea7\u522b\u7684\u5168\u5c40\u6570\u636e\uff0c\u5bf9\u8c61\u9700\u8981\u901a\u8fc7\u6784\u9020\u51fd\u6570\u521d\u59cb\u5316\u5176\u5185\u90e8\u7684&nbsp;<code>vptr<\/code>&nbsp;\u6307\u9488\u6765\u5173\u8054\u865a\u51fd\u6570\u8868\u3002\u82e5\u6784\u9020\u51fd\u6570\u672c\u8eab\u662f\u865a\u51fd\u6570\uff0c\u5219\u8c03\u7528\u5b83\u65f6\u9700\u8981\u4f9d\u8d56&nbsp;<code>vptr<\/code>\uff0c\u800c&nbsp;<code>vptr<\/code>&nbsp;\u53c8\u9700\u901a\u8fc7\u6784\u9020\u51fd\u6570\u521d\u59cb\u5316\uff0c\u5f62\u6210\u903b\u8f91\u77db\u76fe\u3002 <\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">RAII<\/h2>\n\n\n\n<p>RAII\u5168\u79f0\u662f\u201cResource Acquisition is Initialization\u201d\uff1a\u8d44\u6e90\u83b7\u53d6\u5373\u521d\u59cb\u5316\u3002<\/p>\n\n\n\n<p>RAII \u7684\u6838\u5fc3\u601d\u60f3\u662f<strong>\u5c06\u8d44\u6e90\u6216\u8005\u72b6\u6001\u4e0e\u5bf9\u8c61\u7684\u751f\u547d\u5468\u671f\u7ed1\u5b9a<\/strong>\uff0c\u5728\u6784\u9020\u51fd\u6570\u4e2d\u7533\u8bf7\u5206\u914d\u8d44\u6e90\uff0c\u5728\u6790\u6784\u51fd\u6570\u4e2d\u91ca\u653e\u8d44\u6e90\u3002\u56e0\u4e3a C++ \u7684\u8bed\u8a00\u673a\u5236\u4fdd\u8bc1\u4e86\uff0c\u5f53\u4e00\u4e2a\u5bf9\u8c61\u521b\u5efa\u7684\u65f6\u5019\uff0c\u81ea\u52a8\u8c03\u7528\u6784\u9020\u51fd\u6570\uff0c\u5f53\u5bf9\u8c61\u8d85\u51fa\u4f5c\u7528\u57df\u7684\u65f6\u5019\u4f1a\u81ea\u52a8\u8c03\u7528\u6790\u6784\u51fd\u6570\u3002 \u56e0\u6b64\u901a\u8fc7 C++ \u7684\u8bed\u8a00\u673a\u5236\uff0c\u5b9e\u73b0\u8d44\u6e90\u548c\u72b6\u6001\u7684\u5b89\u5168\u7ba1\u7406\uff0c\u667a\u80fd\u6307\u9488\u662f RAII \u6700\u5178\u578b\u7684\u4f8b\u5b50\u3002<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h1 class=\"wp-block-heading\">\u5185\u5b58<\/h1>\n\n\n\n<h2 class=\"wp-block-heading\">new \u548c malloc \u7684\u533a\u522b <\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u7c7b\u578b\u5b89\u5168\u6027\uff1a<\/strong>\n<ul class=\"wp-block-list\">\n<li>new \u662f C++ \u7684\u8fd0\u7b97\u7b26\uff0c\u53ef\u4ee5\u4e3a\u5bf9\u8c61\u5206\u914d\u5185\u5b58\u5e76\u8c03\u2f64\u76f8\u5e94\u7684\u6784\u9020\u51fd\u6570<\/li>\n\n\n\n<li>malloc \u662f C \u8bed\u2f94\u5e93\u51fd\u6570\uff0c\u53ea\u5206\u914d\u6307\u5b9a\u5927\u5c0f\u7684\u5185\u5b58\u5757\uff0c\u4e0d\u4f1a\u8c03\u7528\u6784\u9020\u51fd\u6570<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>\u8fd4\u56de\u7c7b\u578b\uff1a<\/strong>\n<ul class=\"wp-block-list\">\n<li>new \u8fd4\u56de\u7684\u662f\u5177\u4f53\u7c7b\u578b\u7684\u6307\u9488\uff0c\u4e0d\u9700\u8981\u8fdb\u2f8f\u7c7b\u578b\u8f6c\u6362<\/li>\n\n\n\n<li>malloc \u8fd4\u56de\u7684\u662f void*\uff0c\u9700\u8981\u8fdb\u2f8f\u7c7b\u578b\u8f6c\u6362\uff0c\u56e0\u4e3a\u5b83\u4e0d\u77e5\u9053\u6240\u5206\u914d\u5185\u5b58\u7684\u2f64\u9014<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>\u5185\u5b58\u5206\u914d\u5931\u8d25\u65f6\u7684\u884c\u4e3a\uff1a<\/strong>\n<ul class=\"wp-block-list\">\n<li>new \u5728\u5185\u5b58\u5206\u914d\u5931\u8d25\u65f6\u4f1a\u629b\u51fa std::bad_alloc \u5f02\u5e38 <\/li>\n\n\n\n<li>malloc \u5728\u5185\u5b58\u5206\u914d\u5931\u8d25\u65f6\u8fd4\u56de NULL  <\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>\u5185\u5b58\u5757\u5927\u5c0f\uff1a<\/strong>\n<ul class=\"wp-block-list\">\n<li>new \u53ef\u4ee5\u2f64\u4e8e\u52a8\u6001\u5206\u914d\u6570\u7ec4\uff0c\u5e76\u77e5\u9053\u6570\u7ec4\u2f24\u2f29<\/li>\n\n\n\n<li>malloc \u53ea\u662f\u5206\u914d\u6307\u5b9a\u2f24\u2f29\u7684\u5185\u5b58\u5757\uff0c\u4e0d\u4e86\u89e3\u6240\u5206\u914d\u5185\u5b58\u5757\u7684\u5177\u4f53\u2f64\u9014<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>\u91ca\u653e\u5185\u5b58\u7684\u65b9\u5f0f\uff1a<\/strong>\n<ul class=\"wp-block-list\">\n<li>delete \u4f1a\u8c03\u2f64\u5bf9\u8c61\u7684\u6790\u6784\u51fd\u6570\uff0c\u7136\u540e\u91ca\u653e\u5185\u5b58<\/li>\n\n\n\n<li>free \u53ea\u662f\u7b80\u5355\u5730\u91ca\u653e\u5185\u5b58\u5757\uff0c\u4e0d\u4f1a\u8c03\u2f64\u5bf9\u8c61\u7684\u6790\u6784\u51fd\u6570<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">\u5bf9\u5e94\u4e0a\u65b9\uff0cdelete \u548c free \u6709\u4ec0\u4e48\u533a\u522b\uff1f<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u7c7b\u578b\u5b89\u5168\u6027\uff1a<\/strong>\n<ul class=\"wp-block-list\">\n<li>delete \u4f1a\u8c03\u2f64\u5bf9\u8c61\u7684\u6790\u6784\u51fd\u6570\uff0c\u786e\u4fdd\u8d44\u6e90\u88ab\u6b63\u786e\u91ca\u653e<\/li>\n\n\n\n<li>free \u4e0d\u4e86\u89e3\u5bf9\u8c61\u7684\u6784\u9020\u548c\u6790\u6784\uff0c\u53ea\u662f\u7b80\u5355\u5730\u91ca\u653e\u5185\u5b58\u5757 <\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>\u5185\u5b58\u5757\u91ca\u653e\u540e\u7684\u884c\u4e3a\uff1a<\/strong>\n<ul class=\"wp-block-list\">\n<li>delete \u91ca\u653e\u7684\u5185\u5b58\u5757\u7684\u6307\u9488\u503c\u4f1a\u88ab\u8bbe\u7f6e\u4e3a nullptr\uff0c\u4ee5\u907f\u514d\u91ce\u6307\u9488<\/li>\n\n\n\n<li>free \u4e0d\u4f1a\u4fee\u6539\u6307\u9488\u7684\u503c\uff0c\u53ef\u80fd\u5bfc\u81f4\u91ce\u6307\u9488\u95ee\u9898<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>\u6570\u7ec4\u7684\u91ca\u653e\uff1a<\/strong>\n<ul class=\"wp-block-list\">\n<li>delete \u53ef\u4ee5\u6b63\u786e\u91ca\u653e\u901a\u8fc7 new[] \u5206\u914d\u7684\u6570\u7ec4<\/li>\n\n\n\n<li>free \u4e0d\u4e86\u89e3\u6570\u7ec4\u7684\u2f24\u2f29\uff0c\u4e0d\u9002\u2f64\u4e8e\u91ca\u653e\u901a\u8fc7 malloc \u5206\u914d\u7684\u6570\u7ec4<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">\u76f8\u8f83\u4e8e malloc\uff0cnew \u9664\u4e86\u5206\u914d\u5185\u5b58\uff0c\u8fd8\u6709\u5176\u4ed6\u989d\u5916\u7684\u64cd\u4f5c\u5417\uff1f <\/h3>\n\n\n\n<p>\u5982\u679c\u5206\u914d\u7684\u662f\u4e00\u4e2a\u5bf9\u8c61\uff0c<code>new<\/code> \u4e0d\u4ec5\u5206\u914d\u5185\u5b58\uff0c\u8fd8\u4f1a<strong>\u8c03\u7528\u5bf9\u8c61\u7684\u6784\u9020\u51fd\u6570<\/strong>\u6765\u521d\u59cb\u5316\u8be5\u5bf9\u8c61\u3002<\/p>\n\n\n\n<p>Q\uff1a\u90a3\u4e48 new \u5b9e\u9645\u4e0a\u662f\u505a\u4e86\u4e24\u4ef6\u4e8b\uff1a\u2f00\u4e2a\u662f\u5206\u914d\u5185\u5b58\uff0c\u2f00\u4e2a\u662f\u8c03\u2f64\u5b9e\u4f8b\u7684\u6784\u9020\u51fd\u6570\uff0c\u90a3\u6709\u4e86\u89e3\u8fc7 new \u53ef\u4ee5\u53ea\u8fdb\u2f8f\u4e00\u4e2a\u64cd\u4f5c\u5417\uff1f\u2f50\u5982\u53ea\u5206\u914d\u5185\u5b58\u4e0d\u8c03\u2f64\u6784\u9020\u51fd\u6570\uff0c\u6216\u8005\u53ea\u8c03\u2f64\u6784\u9020\u51fd\u6570\u4e0d\u5206\u914d\u5185\u5b58\uff1f<\/p>\n\n\n\n<p>A\uff1anew \u5176\u5b9e\u53ef\u4ee5\u62c6\u5206\u6210\u4e24\u4e2a\u72ec\u7acb\u7684\u64cd\u4f5c\uff1a<strong>\u5206\u914d\u5185\u5b58<\/strong>\u548c<strong>\u8c03\u7528\u6784\u9020\u51fd\u6570<\/strong> <\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u5b9e\u73b0<strong>\u53ea\u5206\u914d\u5185\u5b58<\/strong>\uff1a\u6211\u4eec\u53ef\u4ee5\u76f4\u63a5\u8c03\u7528 <code>operator new<\/code>\uff0c\u5b83\u53ea\u8d1f\u8d23\u5206\u914d\u5185\u5b58\uff0c\u800c\u4e0d\u8c03\u7528\u6784\u9020\u51fd\u6570\uff0c\u8fd9\u6837\u6211\u4eec\u5f97\u5230\u4e86\u4e00\u5757\u539f\u59cb\u5185\u5b58\uff0c\u4f46\u5bf9\u8c61\u672a\u521d\u59cb\u5316\uff1a<code>void* memory = operator new(sizeof(Test));<\/code><\/li>\n\n\n\n<li>\u5b9e\u73b0<strong>\u53ea<strong>\u8c03\u7528\u6784\u9020\u51fd\u6570<\/strong><\/strong>\uff1a\u5982\u679c\u5df2\u7ecf\u6709\u4e00\u5757\u5408\u9002\u7684\u5185\u5b58\uff0c\u6211\u4eec\u53ef\u4ee5\u4f7f\u7528 <code>placement new<\/code>\uff08\u5b9a\u4f4d new\uff09\uff0c\u5b83\u4f1a\u5728\u6307\u5b9a\u7684\u5185\u5b58\u5730\u5740\u4e0a\u8c03\u7528\u6784\u9020\u51fd\u6570\uff1a<code>char buffer[sizeof(Test)]; Test* obj = new (buffer) Test(); <\/code><\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h1 class=\"wp-block-heading\">STL<\/h1>\n\n\n\n<h2 class=\"wp-block-heading\">vector \u5bb9\u5668\u7684\u6269\u5bb9\u673a\u5236<\/h2>\n\n\n\n<p>\u5f53 vector \u5bb9\u5668\u7684 capacity \u548c size \u76f8\u7b49\u65f6\uff0cvector \u5c31\u4f1a\u6269\u5bb9\uff0c\u6709\u4e24\u79cd\u6269\u5bb9\u7b56\u7565\uff1a<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u56fa\u5b9a\u6269\u5bb9<\/strong>\uff08\u7ebf\u6027\u6269\u5bb9\uff09\uff1a\u6bcf\u6b21\u6269\u5bb9\u7684\u65f6\u5019\u5728\u539f capacity \u7684\u57fa\u7840\u4e0a\u52a0\u4e0a\u56fa\u5b9a\u7684\u5bb9\u91cf\uff0c\u2f50\u5982\u521d\u59cb capacity \u4e3a100\uff0c\u6269\u5bb9\u2f00\u6b21\u4e3a capacity + 20\uff0c\u518d\u6269\u5bb9\u4ecd\u7136\u4e3a capacity + 20\u3002\n<ul class=\"wp-block-list\">\n<li>\u4f18\u70b9\uff1a\u7531\u4e8e\u589e\u957f\u5e45\u5ea6\u56fa\u5b9a\uff0c\u4e0d\u4f1a\u6709\u52a0\u500d\u6269\u5bb9\u5e26\u6765\u7684\u5927\u5757\u7a7a\u95f2\u7a7a\u95f4\uff0c\u5373\u56fa\u5b9a\u6269\u5bb9\u2f45\u5f0f\u7a7a\u95f4\u5229\u7528\u7387\u6bd4\u8f83\u9ad8\u3002<\/li>\n\n\n\n<li>\u7f3a\u70b9\uff1a\u6269\u5bb9\u9891\u7387\u66f4\u9ad8\uff0c\u6bcf\u6b21\u6269\u5bb9\u65f6\u90fd\u8981\u6267\u884c\u6570\u636e\u62f7\u8d1d\uff0c\u9891\u7e41\u8fdb\u884c\u5185\u5b58\u5206\u914d\uff0c\u5e26\u6765\u989d\u5916\u7684\u6027\u80fd\u635f\u8017\u3002<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>\u52a0\u500d\u6269\u5bb9<\/strong>\uff08\u6307\u6570\u6269\u5bb9\uff09\uff1a\u6bcf\u6b21\u6269\u5bb9\u7684\u65f6\u5019\u539f capacity \u7ffb\u4e00\u500d\uff0c\u6bd4\u5982\u521d\u59cb capcity = 100\uff0c\u6269\u5bb9\u2f00\u6b21\u53d8\u4e3a 200\uff0c\u518d\u6269\u5bb9\u53d8\u4e3a 400\u3002\n<ul class=\"wp-block-list\">\n<li>\u4f18\u70b9\uff1a\u4f7f\u5f97\u6b63\u5e38\u60c5\u51b5\u4e0b\u6dfb\u52a0\u5143\u7d20\u9700\u8981\u6269\u5bb9\u7684\u6b21\u6570\u5927\u5927\u51cf\u5c11\uff08\u9884\u7559\u7a7a\u95f4\u8f83\u591a\uff09\uff0c\u65f6\u95f4\u590d\u6742\u5ea6\u66f4\u4f4e\u3002<\/li>\n\n\n\n<li>\u7f3a\u70b9\uff1a\u56e0\u4e3a\u6bcf\u6b21\u6269\u5bb9\u7a7a\u95f4\u90fd\u7ffb\u500d\uff0c\u53ef\u80fd\u5bfc\u81f4\u5f88\u591a\u7a7a\u95f4\u6ca1\u6709\u5f97\u5230\u5229\u7528\uff0c\u7a7a\u95f4\u5229\u2f64\u7387\u4e0d\u5982\u56fa\u5b9a\u6269\u5bb9\uff08\u4f46\u662f\u5728\u5b9e\u9645\u5e94\u2f64\u4e2d\uff0c\u2f00\u822c\u91c7\u2f64\u7a7a\u95f4\u6362\u65f6\u95f4\u7684\u7b56\u7565\uff09\u3002<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">\u521a\u624d\u63d0\u5230\u4e862\u500d\u6269\u5bb9\uff0c\u90a3\u4e3a\u4ec0\u4e48\u662f2\u500d\uff0c3\u500d\u53ef\u4ee5\u5417\uff1f<\/h3>\n\n\n\n<p>\u867d\u7136\u53ef\u4ee5\u9009\u62e93\u500d\u6216\u80051.5\u500d\uff0c\u4f46\u5927\u591a\u6570 STL \u5b9e\u73b0\u90fd\u9009\u62e92\u500d\uff0c\u4e3b\u8981\u539f\u56e0\u6709\u4ee5\u4e0b\u51e0\u70b9\uff1a<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u907f\u514d\u9891\u7e41\u7684\u5185\u5b58\u91cd\u65b0\u5206\u914d<\/strong>\n<ul class=\"wp-block-list\">\n<li>\u5982\u679c\u6269\u5bb9\u592a\u5c0f\uff0c\u4f8b\u59821.5\u500d\uff1a\u5f53 <code>vector<\/code> \u9891\u7e41\u589e\u957f\u65f6\uff0c\u9700\u8981\u591a\u6b21\u91cd\u65b0\u5206\u914d\u5185\u5b58\u5e76\u62f7\u8d1d\u5143\u7d20\uff0c\u589e\u52a0\u6027\u80fd\u5f00\u9500 <\/li>\n\n\n\n<li>\u5982\u679c\u6269\u5bb9\u592a\u5927\uff0c\u4f8b\u59823\u500d\uff1a\u53ef\u80fd\u4f1a\u5bfc\u81f4<strong>\u5185\u5b58\u6d6a\u8d39<\/strong>\uff0c\u7279\u522b\u662f\u5728\u5927\u89c4\u6a21\u6570\u636e\u5e94\u7528\u573a\u666f\u4e0b <\/li>\n\n\n\n<li>\u6240\u4ee5\uff0c2\u500d\u6269\u5bb9\u662f\u4e00\u4e2a<strong>\u65f6\u95f4\u590d\u6742\u5ea6\u548c\u7a7a\u95f4\u5229\u7528\u7387\u7684\u5e73\u8861\u70b9<\/strong><\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>\u7b26\u5408\u73b0\u4ee3 CPU \u7f13\u5b58\u4f18\u5316<\/strong>\n<ul class=\"wp-block-list\">\n<li>\u73b0\u4ee3 CPU \u91c7\u7528 <strong>\u7f13\u5b58\u884c\u4f18\u5316<\/strong>\uff0c\u901a\u5e38<strong>2\u500d\u589e\u957f\u66f4\u7b26\u5408 CPU \u9884\u53d6\u548c\u5185\u5b58\u5bf9\u9f50\u673a\u5236<\/strong>\uff0c\u80fd\u591f\u51cf\u5c11\u7f13\u5b58\u5931\u6548\uff0c\u63d0\u9ad8\u8bbf\u95ee\u6548\u7387<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>\u517c\u5bb9 <code>malloc<\/code> \/ <code>new<\/code> \u7684\u5185\u5b58\u5206\u914d\u7b56\u7565<\/strong>\n<ul class=\"wp-block-list\">\n<li><code>malloc<\/code> \u548c <code>operator new<\/code> \u5728\u5e95\u5c42\u7ba1\u7406\u5185\u5b58\u65f6\uff0c\u901a\u5e38\u4f1a\u91c7\u7528<strong>2\u7684\u5e42\u6b21\u5206\u914d\u7b56\u7565<\/strong>\uff08\u4f8b\u5982 <code>8B \u2192 16B \u2192 32B \u2192 64B ...<\/code>\uff09\uff0c2\u500d\u6269\u5bb9\u66f4\u7b26\u5408 <code>malloc<\/code> \u7684\u5de5\u4f5c\u65b9\u5f0f\uff0c\u51cf\u5c11\u788e\u7247\u5316\u95ee\u9898<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">vector \u7684\u521d\u59cb\u5bb9\u91cf\u662f\u591a\u5c11\uff1f\u4ec0\u4e48\u65f6\u5019\u4f1a\u8fdb\u884c\u521d\u6b21\u6269\u5bb9\uff1f<\/h3>\n\n\n\n<p>\u521d\u59cb\u5bb9\u91cf\u53d6\u51b3\u4e8e STL \u7684\u5177\u4f53\u5b9e\u73b0\uff0c\u4e00\u822c\u6765\u8bf4\u521d\u59cb\u5bb9\u91cf\u4e3a0\u3002<\/p>\n\n\n\n<p>\u53ea\u6709\u5f53\u63d2\u5165\u7b2c\u4e00\u4e2a\u5143\u7d20\u65f6\uff0c\u624d\u4f1a\u8fdb\u884c\u9996\u6b21\u6269\u5bb9\u3002<\/p>\n\n\n\n<h4 class=\"wp-block-heading\">\u4e3a\u4ec0\u4e48\u53ea\u6709\u5f53\u63d2\u5165\u7b2c\u4e00\u4e2a\u5143\u7d20\u65f6\uff0c\u624d\u4f1a\u8fdb\u884c\u9996\u6b21\u6269\u5bb9\uff1f\u96be\u9053\u4e0d\u662f\u5f53 size == capacity \u65f6\u5c31\u8981\u6269\u5bb9\u5417\uff1f\u521d\u59cb vector \u5927\u5c0f\u548c\u5bb9\u91cf\u90fd\u4e3a0\uff0c\u4e3a\u4ec0\u4e48\u4e0d\u76f4\u63a5\u6269\u5bb9\uff1f<\/h4>\n\n\n\n<p>\u56e0\u4e3a C++ STL \u91c7\u7528<strong>\u61d2\u52a0\u8f7d<\/strong>\u7b56\u7565\uff0c\u53ea\u6709\u5728\u9700\u8981\u65f6\u624d\u5206\u914d\u5185\u5b58\u3002\u56e0\u6b64\u4e00\u5f00\u59cb vector \u8fde\u5185\u5b58\u90fd\u6ca1\u6709\uff0c\u5f53\u7136\u5c31\u65e0\u6cd5\u6269\u5bb9\u4e86\u3002\u53ea\u6709\u5f53\u7b2c\u4e00\u4e2a\u5143\u7d20\u63d2\u5165\u65f6\uff0cvector \u624d\u88ab\u5206\u914d\u5185\u5b58\uff0c\u8fd9\u65f6\u8fdb\u884c\u6269\u5bb9\u3002<\/p>\n\n\n\n<h4 class=\"wp-block-heading\">\u521d\u6b21\u6269\u5bb9\u540e\uff0c\u5bb9\u91cf\u662f\u591a\u5c11\uff1f<\/h4>\n\n\n\n<p>\u521d\u6b21\u6269\u5bb9\u540e\uff0c\u5bb9\u91cf\u4e00\u822c\u662f1\uff0c\u540e\u7eed\u63092\u500d\u9012\u589e\u3002<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">\u53cc\u5411\u94fe\u8868 list \u7684 front() \u548c begin() \u533a\u522b<\/h2>\n\n\n\n<p><code>front()<\/code> \u76f4\u63a5\u8fd4\u56de<strong>\u7b2c\u4e00\u4e2a\u5143\u7d20\u7684\u5f15\u7528<\/strong>\uff0c\u53ef\u4ee5<strong>\u76f4\u63a5\u8bbf\u95ee\u6216\u4fee\u6539<\/strong>\u3002\u66f4\u52a0\u7b80\u6d01\uff0c\u4e0d\u9700\u8981\u89e3\u5f15\u7528\u3002\u9002\u7528\u4e8e<strong>\u4ec5\u8bbf\u95ee\u6216\u4fee\u6539\u7b2c\u4e00\u4e2a\u5143\u7d20<\/strong>\u7684\u60c5\u51b5\uff0c\u800c\u4e0d\u6d89\u53ca\u904d\u5386\u3002<\/p>\n\n\n\n<p><code>begin()<\/code> \u8fd4\u56de\u7684\u662f<strong>\u6307\u5411\u7b2c\u4e00\u4e2a\u5143\u7d20\u7684\u8fed\u4ee3\u5668<\/strong>\uff0c\u9700\u8981\u4f7f\u7528 <code>*<\/code> \u8fdb\u884c\u89e3\u5f15\u7528\u624d\u80fd\u8bbf\u95ee\u503c\u3002\u8fed\u4ee3\u5668\u53ef\u4ee5<strong>\u7528\u4e8e\u904d\u5386<\/strong>\u6574\u4e2a\u94fe\u8868\uff0c\u9002\u7528\u4e8e\u9700\u8981\u4fee\u6539\u6216\u904d\u5386\u5143\u7d20\u7684\u60c5\u51b5\u3002<\/p>\n\n\n\n<p>\u5982\u679c\u9700\u8981\u4fee\u6539\u7b2c\u4e00\u4e2a\u5143\u7d20\uff1a<code>myList.front() = 100;<\/code> \u7b49\u4ef7\u4e8e <code>*myList.begin() = 100;<\/code><\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h1 class=\"wp-block-heading\">\u65b0\u7279\u6027<\/h1>\n\n\n\n<h2 class=\"wp-block-heading\">lock_guard\/unique_lock\/shared_lock<\/h2>\n\n\n\n<p><strong>lock_guard<\/strong> \u548c <strong>unique_lock<\/strong> \u90fd\u662f C++11\u6807\u51c6\u5e93\u63d0\u4f9b\u7684\u4e92\u65a5\u9501 RAII \u5c01\u88c5\u5de5\u5177\uff0c\u7528\u4e8e\u5b9e\u73b0\u4e92\u65a5\u8bbf\u95ee\u3002<\/p>\n\n\n\n<p>\u521b\u5efa\u8fd9\u4e24\u4e2a\u5bf9\u8c61\u65f6\uff0c\u5b83\u5c06\u5c1d\u8bd5\u83b7\u53d6\u63d0\u4f9b\u7ed9\u5b83\u7684\u4e92\u65a5\u9501\u7684\u6240\u6709\u6743\uff0c\u800c\u5f53\u63a7\u5236\u6d41\u79bb\u5f00\u5bf9\u8c61\u7684\u4f5c\u2f64\u57df\u65f6\uff0c<br>\u4f1a\u6267\u884c\u6790\u6784\u5e76\u91ca\u653e\u4e92\u65a5\u91cf\u3002 <\/p>\n\n\n\n<p>\u4f46\u5b83\u4eec\u6709\u4e00\u4e9b\u4e0d\u540c\u4e4b\u5904\uff1a<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>lock_guard \u662f\u57fa\u4e8e\u4e92\u65a5\u9501 mutex \u5b9e\u73b0\u7684\uff0cunique_lock \u5b9e\u73b0\u7684\u662f\u4e00\u4e2a\u66f4\u901a\u7528\u7684\u9501\uff0c\u53ef\u4ee5\u7528\u4e8e\u4e0d\u540c\u7c7b\u578b\u7684\u9501\uff08\u5982 mutex\u3001recursive_mutex\u3001timed_mutex \u7b49\uff09\u3002<\/li>\n\n\n\n<li>\u56e0\u6b64\uff0cunique_lock \u63d0\u4f9b\u4e86\u66f4\u591a\u7684\u63a7\u5236\u9501\u7684\u884c\u4e3a\uff0c\u6bd4\u5982\u9501\u8d85\u65f6\u3001\u4e0d\u9501\u5b9a\u3001\u6761\u4ef6\u53d8\u91cf\u7b49\u3002<\/li>\n\n\n\n<li>unique_lock \u6bd4 lock_guard \u66f4\u91cd\uff0c\u56e0\u4e3a\u5b83\u6709\u66f4\u591a\u7684\u529f\u80fd\uff0c\u66f4\u591a\u7684\u5f00\u9500\u3002<\/li>\n\n\n\n<li>lock_guard \u662f\u4e0d\u53ef\u79fb\u52a8\u7684\uff0c\u5373\u4e0d\u80fd\u62f7\u8d1d\u3001\u8d4b\u503c\u3001\u79fb\u52a8\uff0c\u53ea\u80fd\u901a\u8fc7\u6784\u9020\u51fd\u6570\u521d\u59cb\u5316\u548c\u6790\u6784\u51fd\u6570\u9500\u6bc1\uff0cunique_lock \u662f\u53ef\u79fb\u52a8\u7684\uff0c\u53ef\u4ee5\u62f7\u8d1d\u3001\u8d4b\u503c\u3001\u79fb\u52a8\u3002<\/li>\n\n\n\n<li>unique_lock \u652f\u6301\u624b\u52a8\u89e3\u9501\uff0c\u800c lock_guard \u4e0d\u652f\u6301\u624b\u52a8\u89e3\u9501\uff0c\u53ea\u80fd\u7b49\u4f5c\u7528\u57df\u7ed3\u675f\u7531\u6790\u6784\u51fd\u6570\u81ea\u52a8\u89e3\u9501\u3002<\/li>\n<\/ul>\n\n\n\n<p><strong>shared_lock <\/strong>\u57fa\u4e8e <strong>shared_mutex<\/strong>\uff0c\u662f C++14 \u5f15\u5165\u7684\u65b0\u7279\u6027\uff0c\u5141\u8bb8\u591a\u4e2a\u7ebf\u7a0b<strong>\u5171\u4eab\u8bfb\u53d6<\/strong>\uff0c\u4f46\u53ea\u6709\u4e00\u4e2a\u7ebf\u7a0b\u53ef\u4ee5<strong>\u72ec\u5360\u5199\u5165<\/strong>\u3002<br>\u7279\u70b9\uff1a<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u9002\u7528\u4e8e<strong>\u8bfb\u591a\u5199\u5c11<\/strong>\u7684\u573a\u666f <\/li>\n\n\n\n<li>\u5141\u8bb8\u591a\u4e2a\u7ebf\u7a0b\u540c\u65f6\u83b7\u53d6<strong>\u5171\u4eab\u9501<\/strong>\uff08<code>shared_lock<\/code>\uff09<\/li>\n\n\n\n<li>\u4f46\u5199\u9501\uff08<code>unique_lock<\/code>\uff09\u4f1a\u963b\u585e\u6240\u6709\u7684\u8bfb\u9501\uff0c\u786e\u4fdd\u5199\u5165\u5b89\u5168<\/li>\n<\/ul>\n\n\n\n<p>\u5176\u4e2d\uff0c\u8bfb\u5199\u9501 <strong>shared_mutex<\/strong> \u4e5f\u53eb\u5171\u4eab-\u72ec\u5360\u9501\u3002\u5f53\u8bfb\u5199\u9501\u4ee5\u8bfb\u6a21\u5f0f\u9501\u4f4f\u65f6\uff0c\u5b83\u662f\u4ee5<strong>\u5171\u4eab<\/strong>\u6a21\u5f0f\u9501\u4f4f\u7684\uff1b\u5f53\u5b83\u4ee5\u5199\u6a21\u5f0f\u9501\u4f4f\u65f6\uff0c\u5b83\u662f\u4ee5<strong>\u72ec\u5360<\/strong>\u6a21\u5f0f\u9501\u4f4f\u7684\u3002\u53ea\u6709\u4e00\u4e2a\u7ebf\u7a0b\u53ef\u4ee5\u5360\u6709\u5199\u6a21\u5f0f\u7684\u8bfb\u5199\u9501\uff0c\u4f46\u662f\u53ef\u4ee5\u6709\u591a\u4e2a\u7ebf\u7a0b\u5360\u6709\u8bfb\u6a21\u5f0f\u7684\u8bfb\u5199\u9501\u3002<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">\u667a\u80fd\u6307\u9488<\/h2>\n\n\n\n<p>\u667a\u80fd\u6307\u9488\u662f\u4e3a\u4e86\u89e3\u51b3\u52a8\u6001\u5206\u914d\u5185\u5b58\u5bfc\u81f4\u5185\u5b58\u6cc4\u9732\u548c\u591a\u6b21\u91ca\u653e\u540c\u2f00\u5185\u5b58\u6240\u63d0\u51fa\u7684\uff0cC++ \u7684\u667a\u80fd\u6307\u9488\u4e3b\u8981\u6709\u4e09\u7c7b\uff1a<code>unique_ptr<\/code>\u3001<code>shared_ptr<\/code> \u548c <code>weak_ptr<\/code>\u3002<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>unique_ptr\uff1a<\/strong><code>unique_ptr<\/code> \u662f<strong>\u72ec\u5360\u6240\u6709\u6743<\/strong>\u7684\u667a\u80fd\u6307\u9488\uff0c\u8868\u793a\u6307\u9488\u6240\u7ba1\u7406\u7684\u5bf9\u8c61\u53ea\u80fd\u7531\u4e00\u4e2a <code>unique_ptr<\/code> \u62e5\u6709\u3002\n<ul class=\"wp-block-list\">\n<li>\u5c01\u88c5\u4e86\u6307\u5411\u5185\u5b58\u7684\u539f\u751f\u6307\u9488\uff0c\u5728\u5bf9\u8c61\u79bb\u5f00\u4f5c\u7528\u57df\u65f6\u81ea\u52a8\u8c03\u7528\u6790\u6784\u51fd\u6570\u91ca\u653e\u8d44\u6e90\u3002<\/li>\n\n\n\n<li>\u4e0d\u80fd\u88ab\u590d\u5236\uff0c\u5373\u6ca1\u6709\u62f7\u8d1d\u6784\u9020\u548c\u62f7\u8d1d\u8d4b\u503c\u8fd0\u7b97\u7b26\uff0c\u652f\u6301\u79fb\u52a8\u8bed\u4e49\uff0c\u53ef\u4ee5\u901a\u8fc7 <code>std::move<\/code> \u8f6c\u79fb\u6240\u6709\u6743\u3002<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>shared_ptr\uff1a<\/strong><code>shared_ptr<\/code> \u662f<strong>\u5171\u4eab\u6240\u6709\u6743<\/strong>\u7684\u667a\u80fd\u6307\u9488\uff0c\u591a\u4e2a <code>shared_ptr<\/code> \u53ef\u4ee5<strong>\u5171\u540c\u7ba1\u7406\u540c\u4e00\u5757\u8d44\u6e90<\/strong>\u3002\n<ul class=\"wp-block-list\">\n<li>\u5404\u4e2a\u5171\u4eab\u6307\u9488\u5171\u4eab\u4e00\u4e2a\u63a7\u5236\u5757\uff0c\u5176\u4e2d\u5b58\u50a8\u4e86\uff1a\u539f\u751f\u6307\u9488\u3001\u5f15\u7528\u8ba1\u6570\u3001\u5f31\u5f15\u7528\u8ba1\u6570\uff08\u6709\u591a\u5c11\u4e2a <code>weak_ptr<\/code> \u89c2\u5bdf\u8fd9\u5757\u8d44\u6e90\uff09\u548c\u81ea\u5b9a\u4e49\u5220\u9664\u5668\uff08\u5982\u679c\u63d0\u4f9b\u4e86\u7684\u8bdd\uff09\u3002<\/li>\n\n\n\n<li>\u901a\u8fc7<strong>\u5f15\u7528\u8ba1\u6570<\/strong>\u6765\u7ba1\u7406\u5bf9\u8c61\uff0c\u62f7\u8d1d\u5171\u4eab\u6307\u9488\u65f6\uff0c\u5f15\u7528\u8ba1\u6570\u52a01\uff0c\u88ab\u9500\u6bc1\u65f6\u5f15\u7528\u8ba1\u6570\u51cf\u4e00\u3002<\/li>\n\n\n\n<li>\u53ea\u6709\u5f53\u6240\u6709 <code>shared_ptr<\/code> \u90fd\u88ab\u9500\u6bc1\uff0c\u5bf9\u8c61\u624d\u4f1a\u88ab\u91ca\u653e\u3002<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>weak_ptr\uff1a<\/strong><code>weak_ptr<\/code> \u662f<strong>\u5f31\u5f15\u7528<\/strong>\u6307\u9488\uff0c\u4e0d\u5f71\u54cd <code>shared_ptr<\/code> \u7684\u5f15\u7528\u8ba1\u6570\u3002\n<ul class=\"wp-block-list\">\n<li>\u7ef4\u62a4\u4e00\u4e2a\u6307\u5411 <code>shared_ptr<\/code> \u63a7\u5236\u5757\u7684\u6307\u9488\uff0c\u4e0d\u62e5\u6709\u8d44\u6e90\uff0c\u4e0d\u589e\u52a0\u5f15\u7528\u8ba1\u6570\uff0c\u4ec5\u4ec5\u662f\u89c2\u5bdf <code>shared_ptr<\/code> \u6240\u7ba1\u7406\u7684\u5bf9\u8c61\u662f\u5426\u4ecd\u7136\u5b58\u5728\u3002<\/li>\n\n\n\n<li>\u907f\u514d <code>shared_ptr<\/code> <strong>\u5faa\u73af\u5f15\u7528<\/strong>\u95ee\u9898\uff08\u5373\u4e24\u4e2a <code>shared_ptr<\/code> \u76f8\u4e92\u6307\u5411\uff0c\u5bfc\u81f4\u5f15\u7528\u8ba1\u6570\u65e0\u6cd5\u964d\u4e3a <code>0<\/code>\uff0c\u8d44\u6e90\u6c38\u8fdc\u4e0d\u4f1a\u91ca\u653e\uff09\u3002<\/li>\n\n\n\n<li>\u9700\u8981 <code>lock()<\/code> \u8f6c\u6362\u4e3a <code>shared_ptr<\/code>\uff0c\u624d\u80fd\u8bbf\u95ee\u8d44\u6e90\u3002 <\/li>\n\n\n\n<li>\u5982\u679c <code>shared_ptr<\/code> \u91ca\u653e\u4e86\u5bf9\u8c61\uff0c<code>weak_ptr<\/code> \u53d8\u4e3a <code>expired()<\/code> \u72b6\u6001\uff0c\u4e0d\u80fd\u8bbf\u95ee\u5df2\u91ca\u653e\u7684\u5bf9\u8c61\u3002<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h1 class=\"wp-block-heading\">\u57fa\u7840<\/h1>\n\n\n\n<h2 class=\"wp-block-heading\">\u9759\u6001\u5c40\u90e8\u53d8\u91cf\\\u5168\u5c40\u53d8\u91cf\\\u5c40\u90e8\u53d8\u91cf<\/h2>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u9759\u6001\u5c40\u90e8\u53d8\u91cf<\/strong>\n<ul class=\"wp-block-list\">\n<li>\u4f5c\u7528\u57df\uff1a\u9650\u5b9a\u5728\u5b9a\u4e49\u5b83\u7684\u51fd\u6570\u5185<\/li>\n\n\n\n<li>\u2f63\u547d\u5468\u671f\uff1a\u4e0e\u7a0b\u5e8f\u7684\u2f63\u547d\u5468\u671f\u76f8\u540c\uff0c\u4f46\u53ea\u80fd\u5728\u5b9a\u4e49\u5b83\u7684\u51fd\u6570\u5185\u90e8\u8bbf\u95ee<\/li>\n\n\n\n<li>\u5173\u952e\u5b57\uff1a\u4f7f\u2f64 static \u5173\u952e\u5b57\u4fee\u9970<\/li>\n\n\n\n<li>\u521d\u59cb\u5316\uff1a\u4ec5\u5728\u7b2c\u2f00\u6b21\u8c03\u2f64\u51fd\u6570\u65f6\u521d\u59cb\u5316\uff0c\u4e4b\u540e\u4fdd\u6301\u5176\u503c<\/li>\n\n\n\n<li>\u9002\u7528\u573a\u666f\uff1a\u5f53\u5e0c\u671b\u5728\u51fd\u6570\u8c03\u2f64\u4e4b\u95f4<strong>\u4fdd\u7559\u53d8\u91cf\u7684\u503c<\/strong>\uff0c\u5e76\u4e14\u4e0d\u5e0c\u671b\u5176\u4ed6\u51fd\u6570\u8bbf\u95ee\u8fd9\u4e2a\u53d8\u91cf\u65f6\uff0c\u53ef\u4ee5\u4f7f\u7528\u9759\u6001\u5c40\u90e8\u53d8\u91cf<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>\u5168\u5c40\u53d8\u91cf<\/strong>\n<ul class=\"wp-block-list\">\n<li>\u4f5c\u7528\u57df\uff1a\u6574\u4e2a\u7a0b\u5e8f<\/li>\n\n\n\n<li>\u2f63\u547d\u5468\u671f\uff1a\u4e0e\u7a0b\u5e8f\u7684\u2f63\u547d\u5468\u671f\u76f8\u540c<\/li>\n\n\n\n<li>\u5173\u952e\u5b57\uff1a\u5b9a\u4e49\u5728\u5168\u5c40\u4f5c\u7528\u57df\uff0c\u4e0d\u4f7f\u2f64\u7279\u5b9a\u5173\u952e\u5b57<\/li>\n\n\n\n<li>\u9002\u7528\u573a\u666f\uff1a\u5f53\u591a\u4e2a\u51fd\u6570\u9700\u8981\u5171\u4eab\u76f8\u540c\u7684\u6570\u636e\u65f6\uff0c\u53ef\u4ee5\u4f7f\u2f64\u5168\u5c40\u53d8\u91cf<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>\u5c40\u90e8\u53d8\u91cf<\/strong>\n<ul class=\"wp-block-list\">\n<li>\u4f5c\u7528\u57df\uff1a\u9650\u5b9a\u5728\u5b9a\u4e49\u5b83\u7684\u5757\uff08\u2f24\u62ec\u53f7\u5185\uff09<\/li>\n\n\n\n<li>\u2f63\u547d\u5468\u671f\uff1a\u5728\u5757\u7ed3\u675f\u65f6\u9500\u6bc1<\/li>\n\n\n\n<li>\u5173\u952e\u5b57\uff1a\u5b9a\u4e49\u5728\u51fd\u6570\u3001\u8bed\u53e5\u5757\u6216\u7c7b\u7684\u6210\u5458\u51fd\u6570\u4e2d<\/li>\n\n\n\n<li>\u9002\u7528\u573a\u666f\uff1a\u5f53\u53d8\u91cf\u53ea\u5728\u67d0\u4e2a\u7279\u5b9a\u4f5c\u2f64\u57df\u5185\u6709\u6548\uff0c\u5e76\u4e14\u4e0d\u9700\u8981\u5176\u4ed6\u4f5c\u7528\u57df\u8bbf\u95ee\u65f6\uff0c\u53ef\u4ee5\u4f7f\u7528\u5c40\u90e8\u53d8\u91cf<\/li>\n<\/ul>\n<\/li>\n<\/ol>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">. \u548c -&gt;\u7684\u533a\u522b<\/h2>\n\n\n\n<p><strong>\u5982\u679c\u662f\u5bf9\u8c61\uff0c\u4f7f\u7528 <\/strong><code><strong>.<\/strong><\/code><strong> \u8bbf\u95ee\u6210\u5458\uff1b\u5982\u679c\u662f\u6307\u9488\uff08\u5305\u62ec\u8fed\u4ee3\u5668\uff09\uff0c\u4f7f\u7528 <code>-&gt;<\/code> \u8bbf\u95ee\u6210\u5458\u3002<\/strong><\/p>\n\n\n\n<p><strong><code>-&gt;<\/code> \u76f8\u5f53\u4e8e\u5148\u5c06\u6307\u9488\u89e3\u5f15\u7528\uff08<code>*ptr<\/code>\uff09\u83b7\u53d6\u5230\u6307\u5411\u7684\u5bf9\u8c61\uff0c\u518d\u4f7f\u7528 <code>.<\/code> \u8fd0\u7b97\u7b26\u8bbf\u95ee\u5bf9\u8c61\u7684\u6210\u5458\u3002<\/strong><\/p>\n\n\n\n<p>\u4e3e\u4e2a\u6817\u5b50\uff1a<\/p>\n\n\n\n<p><code>list&lt;pair&lt;int, int&gt;&gt; m_list; \/\/ \u53cc\u5411\u94fe\u8868\u5b58k\u3001v<\/code><\/p>\n\n\n\n<p><code>unordered_map&lt;int, list&lt;pair&lt;int, int&gt;&gt;::iterator&gt; mp; \/\/ map\u5b58k\u5230list\u8fed\u4ee3\u5668\u7684\u6620\u5c04<\/code><\/p>\n\n\n\n<p>\u90a3\u4e48\u5bf9\u4e8e <code>m_list.back().first<\/code> \u548c <code>mp[key]-&gt;second<\/code> \uff1a<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><code>m_list.back().first<\/code>\n<ul class=\"wp-block-list\">\n<li><code>m_list<\/code> \u662f\u4e00\u4e2a <code>list&lt;pair&lt;int, int&gt;&gt;<\/code>\uff0c\u5373\u5b58\u50a8\u952e\u503c\u5bf9\u7684\u53cc\u5411\u94fe\u8868\u3002<\/li>\n\n\n\n<li><code>m_list.back()<\/code> \u8fd4\u56de\u7684\u662f <code>pair&lt;int, int&gt;<\/code> \u7c7b\u578b\u7684<strong>\u5bf9\u8c61<\/strong>\uff0c\u5373 <code>std::pair&lt;int, int&gt;<\/code>\u3002<\/li>\n\n\n\n<li><code>first<\/code> \u662f <code>std::pair&lt;int, int&gt;<\/code> \u7684\u6210\u5458\u53d8\u91cf\uff0c\u76f4\u63a5\u7528 <code>.<\/code> \u8bbf\u95ee\u3002<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><code>mp[key]-&gt;second<\/code>\n<ul class=\"wp-block-list\">\n<li><code>mp<\/code> \u662f <code>unordered_map&lt;int, list&lt;pair&lt;int, int&gt;&gt;::iterator&gt;<\/code>\uff0c\u5b83\u5b58\u50a8\u7684\u662f\u952e\u503c\u5bf9\u7684\u6620\u5c04\uff0c\u5176\u4e2d\uff1a<code>key<\/code> \u662f <code>int<\/code>\uff0c<code>value<\/code> \u662f\u6307\u5411 <code>m_list<\/code> \u67d0\u4e2a\u8282\u70b9\u7684\u8fed\u4ee3\u5668\u3002<\/li>\n\n\n\n<li>\u7531\u4e8e <code>mp[key]<\/code> \u662f\u4e00\u4e2a<strong>\u8fed\u4ee3\u5668\uff08\u6307\u9488\u7c7b\u578b\uff09<\/strong>\uff0c\u5b83\u6307\u5411\u7684\u662f <code>pair&lt;int, int&gt;<\/code>\uff0c\u56e0\u6b64\u4f7f\u7528 <code>-&gt;<\/code> \u6765\u8bbf\u95ee <code>pair<\/code> \u7684\u6210\u5458\u3002<\/li>\n\n\n\n<li><code>mp[key]-&gt;second<\/code> \u7b49\u4ef7\u4e8e <code>(*mp[key]).second <\/code>\u3002<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n\n<p>ps\uff1a\u5bf9\u8c61\u8c03\u7528\u6210\u5458\u51fd\u6570\u4e5f\u662f\u7528 . \u6bd4\u5982list.front()\uff0c\u56e0\u4e3a\u524d\u9762\u662f<strong>\u5bf9\u8c61<\/strong>\u3002<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">\u6307\u9488\u548c\u5f15\u7528\u7684\u533a\u522b<\/h2>\n\n\n\n<p>\u6307\u9488\u662f\u4e00\u4e2a<strong>\u53d8\u91cf<\/strong>\uff0c\u5b58\u50a8\u7684\u662f\u53e6\u4e00\u4e2a\u53d8\u91cf\u7684\u5730\u5740\uff1b\u5f15\u7528\u662f\u5df2\u6709\u53d8\u91cf\u7684<strong>\u522b\u540d<\/strong>\uff0c\u672c\u8d28\u4e0a\u662f\u4e00\u4e2a\u81ea\u52a8\u89e3\u5f15\u7528\u7684\u6307\u9488\u3002<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li>\u4f7f\u7528\u548c\u64cd\u4f5c\uff1a\n<ul class=\"wp-block-list\">\n<li>\u6307\u9488\uff1a\u53ef\u4ee5\u901a\u8fc7\u89e3\u5f15\u7528\u64cd\u4f5c\u7b26\u6765\u8bbf\u95ee\u6307\u9488\u6307\u5411\u7684\u53d8\u91cf\u7684\u503c\u3002<\/li>\n\n\n\n<li>\u5f15\u2f64\uff1a\u5f15\u7528\u5728\u58f0\u660e\u65f6\u88ab\u521d\u59cb\u5316\uff0c\u5e76\u5728\u6574\u4e2a\u2f63\u547d\u5468\u671f\u4e2d\u2f00\u76f4\u5f15\u7528\u540c\u2f00\u4e2a\u53d8\u91cf\u3002\u4e0d\u9700\u8981\u4f7f\u2f64\u89e3\u5f15\u7528\u64cd\u4f5c\u7b26\uff0c\u56e0\u4e3a\u5f15\u7528\u672c\u8eab\u5c31\u662f\u53d8\u91cf\u7684\u522b\u540d\u3002<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li>\u7a7a\u503c\u548c\u7a7a\u5f15\u7528\uff1a\n<ul class=\"wp-block-list\">\n<li>\u6307\u9488\u53ef\u4ee5\u4e3a\u7a7a\uff08nullptr\uff09\uff0c\u8868\u793a\u4e0d\u6307\u5411\u4efb\u4f55\u6709\u6548\u7684\u5730\u5740\u3002<\/li>\n\n\n\n<li>\u5f15\u7528\u5fc5\u987b\u5728\u58f0\u660e\u65f6\u521d\u59cb\u5316\uff0c\u5e76\u4e14\u4e0d\u80fd\u5728\u540e\u7eed\u6539\u53d8\u7ed1\u5b9a\u7684\u5bf9\u8c61\u3002\u56e0\u6b64\uff0c\u6ca1\u6709\u7a7a\u5f15\u7528\u7684\u6982\u5ff5\u3002<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li>\u53ef\u53d8\u6027\uff1a\n<ul class=\"wp-block-list\">\n<li>\u6307\u9488\uff1a\u53ef\u4ee5\u6539\u53d8\u6307\u9488\u7684\u6307\u5411\uff0c\u4f7f\u5176\u6307\u5411\u4e0d\u540c\u7684\u5185\u5b58\u5730\u5740\u3002<\/li>\n\n\n\n<li>\u5f15\u2f64\uff1a\u2f00\u65e6\u5f15\u7528\u88ab\u521d\u59cb\u5316\uff0c\u5b83\u5c06\u2f00\u76f4\u5f15\u7528\u540c\u2f00\u4e2a\u5bf9\u8c61\uff0c\u4e0d\u80fd\u6539\u53d8\u7ed1\u5b9a\u3002<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li>\u7528\u9014\uff1a\n<ul class=\"wp-block-list\">\n<li>\u6307\u9488\uff1a\u901a\u5e38\u7528\u4e8e\u52a8\u6001\u5185\u5b58\u5206\u914d\u3001\u6570\u7ec4\u64cd\u4f5c\u4ee5\u53ca\u51fd\u6570\u53c2\u6570\u4f20\u9012\u3002<\/li>\n\n\n\n<li>\u5f15\u7528\uff1a\u901a\u5e38\u7528\u4e8e\u51fd\u6570\u53c2\u6570\u4f20\u9012\u3001\u64cd\u4f5c\u7b26\u91cd\u8f7d\u4ee5\u53ca\u521b\u5efa\u522b\u540d\u3002<\/li>\n<\/ul>\n<\/li>\n<\/ol>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">\u5e38\u91cf\u6307\u9488\u548c\u6307\u9488\u5e38\u91cf\u7684\u533a\u522b<\/h2>\n\n\n\n<p>\u5e38\u91cf\u6307\u9488\u662f\u6307<strong>\u6307\u9488\u6307\u5411\u7684\u5bf9\u8c61\u662f\u2f00\u4e2a\u5e38\u91cf<\/strong>\uff0c\u5373\u6307\u9488\u6307\u5411\u7684\u5bf9\u8c61\u7684\u503c\u4e0d\u80fd\u88ab\u4fee\u6539\uff0c\u4f46\u6307\u9488\u7684\u503c\uff08\u5730\u5740\uff09\u53ef\u4ee5\u88ab\u4fee\u6539\u3002\uff08\u8bb0\u5fc6\uff1a\u5e38\u91cf\u6307\u9488\uff0c\u9996\u5148\u8981\u5f97\u662f\u5e38\u91cf\uff0c\u5c31\u662f\u6307\u5411\u7684\u503c\u8981\u662f\u4e00\u4e2a\u5e38\u91cf\uff09<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>int x = 10;\nint y = 20;\nconst int* ptr = &amp;x;  \/\/ \u5e38\u91cf\u6307\u9488\u7684const\u5728*\u524d\u9762\n*ptr = 30;            \/\/ \u274c \u9519\u8bef\uff1a\u4e0d\u80fd\u4fee\u6539\u6307\u5411\u7684\u5bf9\u8c61\u7684\u503c\uff08x\u7684\u503c\uff09\nptr = &amp;y;             \/\/ \u2705 \u6b63\u786e\uff1a\u53ef\u4ee5\u4fee\u6539\u6307\u9488\u7684\u6307\u5411\uff08\u6307\u5411y\uff09<\/code><\/pre>\n\n\n\n<p>\u6307\u9488\u5e38\u91cf\u662f\u6307<strong>\u6307\u9488\u672c\u8eab\u662f\u2f00\u4e2a\u5e38\u91cf<\/strong>\uff0c\u5373\u6307\u9488\u672c\u8eab\u7684\u503c\uff08\u5730\u5740\uff09\u4e0d\u80fd\u88ab\u4fee\u6539\uff0c\u4f46\u6307\u9488\u6240\u6307\u5411\u7684\u5bf9\u8c61\u7684\u503c\u53ef\u4ee5\u88ab\u4fee\u6539\uff08\u8bb0\u5fc6\uff1a\u6307\u9488\u5e38\u91cf\uff0c\u5373\u6307\u9488\u662f\u5e38\u91cf\uff09<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>int x = 10;\nint y = 20;\nint* const ptr = &amp;x;  \/\/ \u6307\u9488\u5e38\u91cf\u7684const\u5728*\u540e\u9762\n*ptr = 30;            \/\/ \u2705 \u6b63\u786e\uff1a\u53ef\u4ee5\u4fee\u6539x\u7684\u503c \nptr = &amp;y;             \/\/ \u274c \u9519\u8bef\uff1a\u4e0d\u80fd\u4fee\u6539\u6307\u9488\u7684\u6307\u5411<\/code><\/pre>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\"><\/h2>\n\n\n\n<p><br><\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u9762\u5411\u5bf9\u8c61 \u591a\u6001\u7684\u5e95\u5c42\u5b9e\u73b0 \u591a\u6001\u7684\u5b9e\u73b0\u5206\u4e3a\u9759\u6001\u591a\u6001\u548c\u52a8\u6001\u591a\u6001\uff1a \u90a3\u4e48\u865a\u51fd\u6570\u7684\u5e95\u5c42\u662f\u5982\u4f55\u5b9e\u73b0\u7684\uff1f \u6bcf\u4e2a\u5305\u542b\u865a\u51fd\u6570\u7684 [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[4,87],"tags":[],"class_list":["post-2514","post","type-post","status-publish","format-standard","hentry","category-cpp","category-87"],"_links":{"self":[{"href":"https:\/\/guapicoding.com\/index.php?rest_route=\/wp\/v2\/posts\/2514","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/guapicoding.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/guapicoding.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/guapicoding.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/guapicoding.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=2514"}],"version-history":[{"count":42,"href":"https:\/\/guapicoding.com\/index.php?rest_route=\/wp\/v2\/posts\/2514\/revisions"}],"predecessor-version":[{"id":3489,"href":"https:\/\/guapicoding.com\/index.php?rest_route=\/wp\/v2\/posts\/2514\/revisions\/3489"}],"wp:attachment":[{"href":"https:\/\/guapicoding.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=2514"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/guapicoding.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=2514"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/guapicoding.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=2514"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}