{"id":1610,"date":"2025-03-24T08:50:16","date_gmt":"2025-03-23T23:50:16","guid":{"rendered":"https:\/\/dexall.co.jp\/articles\/?p=1610"},"modified":"2025-03-24T08:50:16","modified_gmt":"2025-03-23T23:50:16","slug":"stdvector%e3%82%92%e5%ae%8c%e5%85%a8%e7%90%86%e8%a7%a3%ef%bc%81%e7%8f%be%e5%a0%b4%e3%81%a7%e4%bd%bf%e3%81%88%e3%82%8b%e5%ae%9f%e8%b7%b5%e7%9a%84%e3%81%aa%e6%b4%bb%e7%94%a8%e6%b3%95%e3%81%a8%e6%9c%80","status":"publish","type":"post","link":"https:\/\/dexall.co.jp\/articles\/?p=1610","title":{"rendered":"std::vector\u3092\u5b8c\u5168\u7406\u89e3\uff01\u73fe\u5834\u3067\u4f7f\u3048\u308b\u5b9f\u8df5\u7684\u306a\u6d3b\u7528\u6cd5\u3068\u6700\u9069\u5316\u30c6\u30af\u30cb\u30c3\u30af15\u9078"},"content":{"rendered":"\n<div class=\"toc\"><br \/>\n<b>Warning<\/b>:  Undefined array key \"is_admin\" in <b>\/home\/xs392991\/dexall.co.jp\/public_html\/articles\/wp-content\/themes\/sango-theme\/library\/gutenberg\/dist\/classes\/Toc.php<\/b> on line <b>116<\/b><br \/>\n<br \/>\n<b>Warning<\/b>:  Undefined array key \"is_category_top\" in <b>\/home\/xs392991\/dexall.co.jp\/public_html\/articles\/wp-content\/themes\/sango-theme\/library\/gutenberg\/dist\/classes\/Toc.php<\/b> on line <b>121<\/b><br \/>\n<br \/>\n<b>Warning<\/b>:  Undefined array key \"is_top\" in <b>\/home\/xs392991\/dexall.co.jp\/public_html\/articles\/wp-content\/themes\/sango-theme\/library\/gutenberg\/dist\/classes\/Toc.php<\/b> on line <b>128<\/b><br \/>\n    <div id=\"toc_container\" class=\"sgb-toc--bullets js-smooth-scroll\" data-dialog-title=\"\u76ee\u6b21\">\n      <p class=\"toc_title\">\u76ee\u6b21 <\/p>\n      <ul class=\"toc_list\">  <li class=\"first\">    <a href=\"#i-0\">std::vector\u3068\u306f\uff1f\u521d\u5fc3\u8005\u3067\u3082\u308f\u304b\u308b\u57fa\u790e\u77e5\u8b58<\/a>    <ul class=\"menu_level_1\">      <li class=\"first\">        <a href=\"#i-1\">\u914d\u5217\u3068vector\u306e\u9055\u3044\u3092\u7406\u89e3\u3057\u3088\u3046<\/a>      <\/li>      <li>        <a href=\"#i-2\">vector\u306e\u30e1\u30e2\u30ea\u7ba1\u7406\u306e\u4ed5\u7d44\u307f<\/a>      <\/li>      <li class=\"last\">        <a href=\"#i-3\">C++11\u4ee5\u964d\u306e\u65b0\u6a5f\u80fd\u3068\u9032\u5316<\/a>      <\/li>    <\/ul>  <\/li>  <li>    <a href=\"#i-4\">std::vector\u306e\u57fa\u672c\u64cd\u4f5c\u30de\u30b9\u30bf\u30fc\u30ac\u30a4\u30c9<\/a>    <ul class=\"menu_level_1\">      <li class=\"first\">        <a href=\"#i-5\">\u8981\u7d20\u306e\u8ffd\u52a0\u3068\u524a\u9664\u3092\u78ba\u5b9f\u306b\u884c\u3046\u65b9\u6cd5<\/a>      <\/li>      <li>        <a href=\"#i-6\">\u30a4\u30c6\u30ec\u30fc\u30bf\u3092\u4f7f\u3063\u305f\u52b9\u7387\u7684\u306a\u64cd\u4f5c\u30c6\u30af\u30cb\u30c3\u30af<\/a>      <\/li>      <li class=\"last\">        <a href=\"#i-7\">\u30e1\u30e2\u30ea\u7ba1\u7406\u306e\u30d9\u30b9\u30c8\u30d7\u30e9\u30af\u30c6\u30a3\u30b9<\/a>      <\/li>    <\/ul>  <\/li>  <li>    <a href=\"#i-8\">\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u3092\u6700\u5927\u5316\u3059\u308b\u6700\u9069\u5316\u30c6\u30af\u30cb\u30c3\u30af<\/a>    <ul class=\"menu_level_1\">      <li class=\"first\">        <a href=\"#i-9\">reserve()\u3092\u4f7f\u3063\u305f\u30e1\u30e2\u30ea\u6700\u9069\u5316\u306e\u5b9f\u8df5<\/a>      <\/li>      <li>        <a href=\"#i-10\">emplace_back()\u3067\u52b9\u7387\u7684\u306b\u8981\u7d20\u3092\u8ffd\u52a0\u3059\u308b<\/a>      <\/li>      <li class=\"last\">        <a href=\"#i-11\">\u4e0d\u8981\u306a\u30b3\u30d4\u30fc\u3092\u9632\u3050\u30e0\u30fc\u30d6\u30bb\u30de\u30f3\u30c6\u30a3\u30af\u30b9\u306e\u6d3b\u7528<\/a>      <\/li>    <\/ul>  <\/li>  <li>    <a href=\"#i-12\">\u5b9f\u52d9\u3067\u3088\u304f\u3042\u308bvector\u306e\u6d3b\u7528\u30b7\u30fc\u30f3<\/a>    <ul class=\"menu_level_1\">      <li class=\"first\">        <a href=\"#i-13\">\u5927\u91cf\u30c7\u30fc\u30bf\u306e\u52b9\u7387\u7684\u306a\u51e6\u7406\u65b9\u6cd5<\/a>      <\/li>      <li>        <a href=\"#i-14\">\u4e26\u5217\u51e6\u7406\u3067\u306e\u5b89\u5168\u306a\u4f7f\u7528\u6cd5<\/a>      <\/li>      <li class=\"last\">        <a href=\"#i-15\">\u30e1\u30e2\u30ea\u30ea\u30fc\u30af\u3092\u9632\u3050RAII\u30d1\u30bf\u30fc\u30f3\u306e\u5b9f\u88c5<\/a>      <\/li>    <\/ul>  <\/li>  <li class=\"last\">    <a href=\"#i-16\">std::vector\u3092\u4f7f\u3046\u969b\u306e\u6ce8\u610f\u70b9\u3068\u56de\u907f\u7b56<\/a>    <ul class=\"menu_level_1\">      <li class=\"first\">        <a href=\"#i-17\">\u30a4\u30c6\u30ec\u30fc\u30bf\u7121\u52b9\u5316\u306e\u7f60\u3068\u5bfe\u51e6\u6cd5<\/a>      <\/li>      <li>        <a href=\"#i-18\">\u30e1\u30e2\u30ea\u65ad\u7247\u5316\u3092\u9632\u3050\u30c6\u30af\u30cb\u30c3\u30af<\/a>      <\/li>      <li class=\"last\">        <a href=\"#i-19\">\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u30dc\u30c8\u30eb\u30cd\u30c3\u30af\u306e\u7279\u5b9a\u3068\u89e3\u6c7a<\/a>      <\/li>    <\/ul>  <\/li><\/ul>\n      <a href=\"#\" class=\"sgb-toc-button js-toc-button\" rel=\"nofollow\" data-open-dialog=\"true\"><i class=\"fa fa-list\"><\/i><span class=\"sgb-toc-button__text\">\u76ee\u6b21\u3078<\/span><\/a>\n    <\/div><\/div><h2 class=\"wp-block-heading\" id=\"i-0\">std::vector\u3068\u306f\uff1f\u521d\u5fc3\u8005\u3067\u3082\u308f\u304b\u308b\u57fa\u790e\u77e5\u8b58<\/h2>\n\n\n\n<p>std::vector\u306f\u3001C++\u6a19\u6e96\u30c6\u30f3\u30d7\u30ec\u30fc\u30c8\u30e9\u30a4\u30d6\u30e9\u30ea\uff08STL\uff09\u3067\u63d0\u4f9b\u3055\u308c\u308b\u52d5\u7684\u914d\u5217\u30b3\u30f3\u30c6\u30ca\u3067\u3059\u3002\u30b5\u30a4\u30ba\u3092\u5b9f\u884c\u6642\u306b\u5909\u66f4\u3067\u304d\u3001\u9023\u7d9a\u3057\u305f\u30e1\u30e2\u30ea\u9818\u57df\u306b\u8981\u7d20\u3092\u683c\u7d0d\u3059\u308b\u7279\u5fb4\u304c\u3042\u308a\u307e\u3059\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-1\">\u914d\u5217\u3068vector\u306e\u9055\u3044\u3092\u7406\u89e3\u3057\u3088\u3046<\/h3>\n\n\n\n<p>\u901a\u5e38\u306e\u914d\u5217\u3068vector\u306b\u306f\u3001\u3044\u304f\u3064\u304b\u306e\u91cd\u8981\u306a\u9055\u3044\u304c\u3042\u308a\u307e\u3059\uff1a<\/p>\n\n\n<div id=\"id-9a968a33-3158-4c40-add7-78c82be16848\">\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><thead><tr><th>\u7279\u5fb4<\/th><th>\u901a\u5e38\u306e\u914d\u5217<\/th><th>std::vector<\/th><\/tr><\/thead><tbody><tr><td>\u30b5\u30a4\u30ba\u5909\u66f4<\/td><td>\u4e0d\u53ef\u80fd\uff08\u56fa\u5b9a\uff09<\/td><td>\u53ef\u80fd\uff08\u52d5\u7684\uff09<\/td><\/tr><tr><td>\u30e1\u30e2\u30ea\u7ba1\u7406<\/td><td>\u624b\u52d5<\/td><td>\u81ea\u52d5<\/td><\/tr><tr><td>\u5883\u754c\u30c1\u30a7\u30c3\u30af<\/td><td>\u306a\u3057<\/td><td>at()\u30e1\u30bd\u30c3\u30c9\u3067\u53ef\u80fd<\/td><\/tr><tr><td>\u30b5\u30a4\u30ba\u53d6\u5f97<\/td><td>\u624b\u52d5\u8a08\u7b97\u5fc5\u8981<\/td><td>size()\u3067\u5373\u6642\u53d6\u5f97<\/td><\/tr><\/tbody><\/table><\/figure>\n<\/div>\n\n\n<p>\u4ee5\u4e0b\u306f\u3001\u914d\u5217\u3068vector\u306e\u57fa\u672c\u7684\u306a\u4f7f\u7528\u4f8b\u3067\u3059\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ \u901a\u5e38\u306e\u914d\u5217\nint normal_array[5] = {1, 2, 3, 4, 5};  \/\/ \u30b5\u30a4\u30ba\u3092\u56fa\u5b9a\u3067\u6307\u5b9a\u3059\u308b\u5fc5\u8981\u304c\u3042\u308b\n\/\/ \u30b5\u30a4\u30ba\u306e\u5909\u66f4\u306f\u4e0d\u53ef\u80fd\n\n\/\/ std::vector\nstd::vector&lt;int&gt; vec = {1, 2, 3, 4, 5};  \/\/ \u521d\u671f\u30b5\u30a4\u30ba\u306f\u81ea\u52d5\u3067\u6c7a\u5b9a\nvec.push_back(6);  \/\/ \u52d5\u7684\u306b\u30b5\u30a4\u30ba\u3092\u62e1\u5f35\u53ef\u80fd<\/pre>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-2\">vector\u306e\u30e1\u30e2\u30ea\u7ba1\u7406\u306e\u4ed5\u7d44\u307f<\/h3>\n\n\n\n<p>vector\u306f\u3001\u4ee5\u4e0b\u306e\u7279\u5fb4\u7684\u306a\u30e1\u30e2\u30ea\u7ba1\u7406\u3092\u884c\u3044\u307e\u3059\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u81ea\u52d5\u7684\u306a\u30e1\u30e2\u30ea\u78ba\u4fdd<\/strong><\/li>\n<\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u8981\u7d20\u8ffd\u52a0\u6642\u306b\u5fc5\u8981\u306b\u5fdc\u3058\u3066\u81ea\u52d5\u7684\u306b\u30e1\u30e2\u30ea\u3092\u78ba\u4fdd<\/li>\n\n\n\n<li>\u901a\u5e38\u3001\u73fe\u5728\u306e\u30b5\u30a4\u30ba\u306e1.5\u500d\u307e\u305f\u306f2\u500d\u306e\u30e1\u30e2\u30ea\u3092\u78ba\u4fdd<\/li>\n<\/ul>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u30e1\u30e2\u30ea\u30ec\u30a4\u30a2\u30a6\u30c8<\/strong><\/li>\n<\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u8981\u7d20\u306f\u9023\u7d9a\u3057\u305f\u30e1\u30e2\u30ea\u9818\u57df\u306b\u914d\u7f6e<\/li>\n\n\n\n<li>\u30ad\u30e3\u30c3\u30b7\u30e5\u30d5\u30ec\u30f3\u30c9\u30ea\u30fc\u306a\u8a2d\u8a08\u306b\u3088\u308a\u9ad8\u901f\u306a\u30a2\u30af\u30bb\u30b9\u304c\u53ef\u80fd<\/li>\n<\/ul>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">std::vector&lt;int&gt; vec;\n\/\/ capacity\u3068size\u306e\u78ba\u8a8d\nstd::cout &lt;&lt; \"Initial capacity: \" &lt;&lt; vec.capacity() &lt;&lt; std::endl;  \/\/ \u521d\u671f\u5bb9\u91cf\nvec.push_back(1);\nstd::cout &lt;&lt; \"After adding one element: \" &lt;&lt; vec.capacity() &lt;&lt; std::endl;  \/\/ \u5bb9\u91cf\u304c\u81ea\u52d5\u3067\u5897\u52a0<\/pre>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-3\">C++11\u4ee5\u964d\u306e\u65b0\u6a5f\u80fd\u3068\u9032\u5316<\/h3>\n\n\n\n<p>C++11\u4ee5\u964d\u3001vector\u306f\u591a\u304f\u306e\u4fbf\u5229\u306a\u6a5f\u80fd\u304c\u8ffd\u52a0\u3055\u308c\u307e\u3057\u305f\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u7d71\u4e00\u521d\u671f\u5316\u69cb\u6587<\/strong><\/li>\n<\/ol>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">std::vector&lt;int&gt; vec{1, 2, 3, 4, 5};  \/\/ \u6ce2\u62ec\u5f27\u306b\u3088\u308b\u521d\u671f\u5316\u304c\u53ef\u80fd<\/pre>\n\n\n\n<ol start=\"2\" class=\"wp-block-list\">\n<li><strong>emplace_back<\/strong><\/li>\n<\/ol>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">struct MyClass {\n    MyClass(int x, std::string str) {}\n};\nstd::vector&lt;MyClass&gt; vec;\nvec.emplace_back(10, \"test\");  \/\/ \u30b3\u30f3\u30b9\u30c8\u30e9\u30af\u30bf\u306e\u5f15\u6570\u3092\u76f4\u63a5\u6e21\u305b\u308b<\/pre>\n\n\n\n<ol start=\"3\" class=\"wp-block-list\">\n<li><strong>\u30c7\u30fc\u30bf\u30a2\u30af\u30bb\u30b9\u306e\u6539\u5584<\/strong><\/li>\n<\/ol>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ \u30c7\u30fc\u30bf\u30dd\u30a4\u30f3\u30bf\u306e\u76f4\u63a5\u53d6\u5f97\nint* data = vec.data();\n\n\/\/ \u7bc4\u56f2\u30d9\u30fc\u30b9\u306efor\u6587\nfor (const auto&amp; element : vec) {\n    \/\/ \u5404\u8981\u7d20\u306b\u5bfe\u3059\u308b\u51e6\u7406\n}<\/pre>\n\n\n\n<ol start=\"4\" class=\"wp-block-list\">\n<li><strong>\u30e0\u30fc\u30d6\u30bb\u30de\u30f3\u30c6\u30a3\u30af\u30b9\u5bfe\u5fdc<\/strong><\/li>\n<\/ol>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">std::vector&lt;std::string&gt; vec1 = {\"hello\", \"world\"};\nstd::vector&lt;std::string&gt; vec2 = std::move(vec1);  \/\/ \u52b9\u7387\u7684\u306a\u30c7\u30fc\u30bf\u79fb\u52d5<\/pre>\n\n\n\n<p>\u3053\u308c\u3089\u306e\u6a5f\u80fd\u306b\u3088\u308a\u3001vector\u306f\u3088\u308a\u4f7f\u3044\u3084\u3059\u304f\u3001\u52b9\u7387\u7684\u306a\u30b3\u30f3\u30c6\u30ca\u3068\u306a\u3063\u3066\u3044\u307e\u3059\u3002\u30e1\u30e2\u30ea\u7ba1\u7406\u306e\u81ea\u52d5\u5316\u3068\u8c4a\u5bcc\u306a\u6a5f\u80fd\u30bb\u30c3\u30c8\u306b\u3088\u308a\u3001\u591a\u304f\u306e\u5834\u9762\u3067\u914d\u5217\u306e\u4ee3\u66ff\u3068\u3057\u3066\u6700\u9069\u306a\u9078\u629e\u80a2\u3068\u306a\u3063\u3066\u3044\u307e\u3059\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"i-4\">std::vector\u306e\u57fa\u672c\u64cd\u4f5c\u30de\u30b9\u30bf\u30fc\u30ac\u30a4\u30c9<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-5\">\u8981\u7d20\u306e\u8ffd\u52a0\u3068\u524a\u9664\u3092\u78ba\u5b9f\u306b\u884c\u3046\u65b9\u6cd5<\/h3>\n\n\n\n<p>vector\u306e\u8981\u7d20\u64cd\u4f5c\u306b\u306f\u8907\u6570\u306e\u30e1\u30bd\u30c3\u30c9\u304c\u7528\u610f\u3055\u308c\u3066\u304a\u308a\u3001\u72b6\u6cc1\u306b\u5fdc\u3058\u3066\u9069\u5207\u306a\u3082\u306e\u3092\u9078\u629e\u3059\u308b\u3053\u3068\u304c\u91cd\u8981\u3067\u3059\u3002<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u8981\u7d20\u306e\u8ffd\u52a0<\/strong><\/li>\n<\/ol>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">std::vector&lt;int&gt; vec;\n\n\/\/ \u672b\u5c3e\u3078\u306e\u8ffd\u52a0\nvec.push_back(10);          \/\/ \u672b\u5c3e\u306b\u8ffd\u52a0\nvec.emplace_back(20);       \/\/ \u672b\u5c3e\u306b\u76f4\u63a5\u69cb\u7bc9\n\n\/\/ \u4efb\u610f\u306e\u4f4d\u7f6e\u3078\u306e\u8ffd\u52a0\nvec.insert(vec.begin(), 5); \/\/ \u5148\u982d\u306b\u8ffd\u52a0\nvec.emplace(vec.begin(), 15); \/\/ \u5148\u982d\u306b\u76f4\u63a5\u69cb\u7bc9\n\n\/\/ \u8907\u6570\u8981\u7d20\u306e\u8ffd\u52a0\nvec.insert(vec.end(), {1, 2, 3}); \/\/ \u672b\u5c3e\u306b\u8907\u6570\u8981\u7d20\u3092\u8ffd\u52a0<\/pre>\n\n\n\n<ol start=\"2\" class=\"wp-block-list\">\n<li><strong>\u8981\u7d20\u306e\u524a\u9664<\/strong><\/li>\n<\/ol>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ \u672b\u5c3e\u306e\u8981\u7d20\u3092\u524a\u9664\nvec.pop_back();\n\n\/\/ \u7279\u5b9a\u4f4d\u7f6e\u306e\u8981\u7d20\u3092\u524a\u9664\nvec.erase(vec.begin());     \/\/ \u5148\u982d\u8981\u7d20\u3092\u524a\u9664\nvec.erase(vec.begin() + 2); \/\/ 3\u756a\u76ee\u306e\u8981\u7d20\u3092\u524a\u9664\n\n\/\/ \u7bc4\u56f2\u524a\u9664\nvec.erase(vec.begin(), vec.begin() + 3); \/\/ \u6700\u521d\u306e3\u8981\u7d20\u3092\u524a\u9664\n\n\/\/ \u5168\u8981\u7d20\u524a\u9664\nvec.clear();<\/pre>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-6\">\u30a4\u30c6\u30ec\u30fc\u30bf\u3092\u4f7f\u3063\u305f\u52b9\u7387\u7684\u306a\u64cd\u4f5c\u30c6\u30af\u30cb\u30c3\u30af<\/h3>\n\n\n\n<p>\u30a4\u30c6\u30ec\u30fc\u30bf\u3092\u4f7f\u7528\u3059\u308b\u3053\u3068\u3067\u3001vector\u306e\u8981\u7d20\u306b\u5bfe\u3057\u3066\u67d4\u8edf\u306a\u64cd\u4f5c\u304c\u53ef\u80fd\u306b\u306a\u308a\u307e\u3059\u3002<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u57fa\u672c\u7684\u306a\u30a4\u30c6\u30ec\u30fc\u30bf\u306e\u4f7f\u7528<\/strong><\/li>\n<\/ol>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">std::vector&lt;int&gt; vec = {1, 2, 3, 4, 5};\n\n\/\/ \u901a\u5e38\u306e\u30a4\u30c6\u30ec\u30fc\u30c8\nfor (auto it = vec.begin(); it != vec.end(); ++it) {\n    std::cout &lt;&lt; *it &lt;&lt; \" \";  \/\/ \u8981\u7d20\u3078\u306e\u30a2\u30af\u30bb\u30b9\n}\n\n\/\/ \u9006\u9806\u30a4\u30c6\u30ec\u30fc\u30c8\nfor (auto it = vec.rbegin(); it != vec.rend(); ++it) {\n    std::cout &lt;&lt; *it &lt;&lt; \" \";  \/\/ \u9006\u9806\u306b\u8981\u7d20\u306b\u30a2\u30af\u30bb\u30b9\n}<\/pre>\n\n\n\n<ol start=\"2\" class=\"wp-block-list\">\n<li><strong>\u30a4\u30c6\u30ec\u30fc\u30bf\u3092\u4f7f\u3063\u305f\u9ad8\u5ea6\u306a\u64cd\u4f5c<\/strong><\/li>\n<\/ol>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\/\/ \u8981\u7d20\u306e\u691c\u7d22\nauto it = std::find(vec.begin(), vec.end(), 3);\nif (it != vec.end()) {\n    \/\/ \u8981\u7d20\u304c\u898b\u3064\u304b\u3063\u305f\u5834\u5408\u306e\u51e6\u7406\n}\n\n\/\/ \u6761\u4ef6\u306b\u57fa\u3065\u304f\u8981\u7d20\u306e\u524a\u9664\nvec.erase(\n    std::remove_if(vec.begin(), vec.end(),\n        [](int x) { return x % 2 == 0; }), \/\/ \u5076\u6570\u3092\u524a\u9664\n    vec.end()\n);\n\n\/\/ \u8981\u7d20\u306e\u4e26\u3073\u66ff\u3048\nstd::sort(vec.begin(), vec.end()); \/\/ \u6607\u9806\u30bd\u30fc\u30c8<\/pre>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-7\">\u30e1\u30e2\u30ea\u7ba1\u7406\u306e\u30d9\u30b9\u30c8\u30d7\u30e9\u30af\u30c6\u30a3\u30b9<\/h3>\n\n\n\n<p>\u52b9\u7387\u7684\u306a\u30e1\u30e2\u30ea\u7ba1\u7406\u306f\u3001vector\u306e\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u306b\u5927\u304d\u304f\u5f71\u97ff\u3057\u307e\u3059\u3002<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u5bb9\u91cf\u306e\u4e8b\u524d\u78ba\u4fdd<\/strong><\/li>\n<\/ol>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">std::vector&lt;int&gt; vec;\nvec.reserve(1000);  \/\/ 1000\u8981\u7d20\u5206\u306e\u30e1\u30e2\u30ea\u3092\u4e8b\u524d\u78ba\u4fdd\n\n\/\/ \u5927\u91cf\u306e\u8981\u7d20\u3092\u8ffd\u52a0\u3059\u308b\u5834\u5408\u3001\u30ea\u30a2\u30ed\u30b1\u30fc\u30b7\u30e7\u30f3\u304c\u767a\u751f\u3057\u306a\u3044\nfor (int i = 0; i &lt; 1000; ++i) {\n    vec.push_back(i);\n}<\/pre>\n\n\n\n<ol start=\"2\" class=\"wp-block-list\">\n<li><strong>\u4e0d\u8981\u306a\u30e1\u30e2\u30ea\u306e\u89e3\u653e<\/strong><\/li>\n<\/ol>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">std::vector&lt;int&gt; vec = {1, 2, 3, 4, 5};\nvec.erase(vec.begin(), vec.begin() + 3); \/\/ \u8981\u7d20\u524a\u9664\u5f8c\n\n\/\/ \u4f59\u5206\u306a\u30e1\u30e2\u30ea\u3092\u89e3\u653e\nvec.shrink_to_fit();<\/pre>\n\n\n\n<ol start=\"3\" class=\"wp-block-list\">\n<li><strong>\u30e1\u30e2\u30ea\u4f7f\u7528\u91cf\u306e\u76e3\u8996<\/strong><\/li>\n<\/ol>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">std::vector&lt;int&gt; vec;\nstd::cout &lt;&lt; \"Size: \" &lt;&lt; vec.size() &lt;&lt; std::endl;     \/\/ \u8981\u7d20\u6570\nstd::cout &lt;&lt; \"Capacity: \" &lt;&lt; vec.capacity() &lt;&lt; std::endl; \/\/ \u78ba\u4fdd\u6e08\u307f\u30e1\u30e2\u30ea\u5bb9\u91cf\n\n\/\/ capacity\u306e\u5909\u5316\u3092\u78ba\u8a8d\nvec.push_back(1);\nstd::cout &lt;&lt; \"New capacity: \" &lt;&lt; vec.capacity() &lt;&lt; std::endl;<\/pre>\n\n\n\n<p>\u5b9f\u88c5\u6642\u306e\u91cd\u8981\u306a\u30dd\u30a4\u30f3\u30c8\uff1a<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>push_back()\u3088\u308a\u3082emplace_back()\u3092\u512a\u5148\u3057\u3066\u4f7f\u7528\u3059\u308b<\/li>\n\n\n\n<li>\u5927\u91cf\u306e\u8981\u7d20\u3092\u8ffd\u52a0\u3059\u308b\u524d\u306breserve()\u3067\u30e1\u30e2\u30ea\u3092\u78ba\u4fdd\u3059\u308b<\/li>\n\n\n\n<li>\u4e0d\u8981\u306a\u30e1\u30e2\u30ea\u306fshrink_to_fit()\u3067\u89e3\u653e\u3059\u308b<\/li>\n\n\n\n<li>\u30a4\u30c6\u30ec\u30fc\u30bf\u306e\u7121\u52b9\u5316\u306b\u6ce8\u610f\u3059\u308b\uff08\u8981\u7d20\u306e\u8ffd\u52a0\u30fb\u524a\u9664\u5f8c\uff09<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"i-8\">\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u3092\u6700\u5927\u5316\u3059\u308b\u6700\u9069\u5316\u30c6\u30af\u30cb\u30c3\u30af<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-9\">reserve()\u3092\u4f7f\u3063\u305f\u30e1\u30e2\u30ea\u6700\u9069\u5316\u306e\u5b9f\u8df5<\/h3>\n\n\n\n<p>\u30e1\u30e2\u30ea\u306e\u518d\u5272\u308a\u5f53\u3066\u306f\u975e\u5e38\u306b\u30b3\u30b9\u30c8\u306e\u9ad8\u3044\u64cd\u4f5c\u3067\u3059\u3002reserve()\u3092\u52b9\u679c\u7684\u306b\u4f7f\u7528\u3059\u308b\u3053\u3068\u3067\u3001\u3053\u306e\u30b3\u30b9\u30c8\u3092\u5927\u5e45\u306b\u524a\u6e1b\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u30e1\u30e2\u30ea\u518d\u5272\u308a\u5f53\u3066\u306e\u5f71\u97ff<\/strong><\/li>\n<\/ol>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">#include &lt;chrono&gt;\n#include &lt;vector&gt;\n\n\/\/ \u30e1\u30e2\u30ea\u518d\u5272\u308a\u5f53\u3066\u306e\u5f71\u97ff\u3092\u6e2c\u5b9a\u3059\u308b\u4f8b\nvoid measure_reallocation() {\n    const int n = 100000;\n\n    \/\/ reserve()\u306a\u3057\u306e\u5834\u5408\n    auto start = std::chrono::high_resolution_clock::now();\n    std::vector&lt;int&gt; vec1;\n    for (int i = 0; i &lt; n; ++i) {\n        vec1.push_back(i);\n        if (i % 10000 == 0) {\n            std::cout &lt;&lt; \"Capacity: \" &lt;&lt; vec1.capacity() &lt;&lt; std::endl;\n        }\n    }\n    auto end1 = std::chrono::high_resolution_clock::now();\n\n    \/\/ reserve()\u4f7f\u7528\u306e\u5834\u5408\n    start = std::chrono::high_resolution_clock::now();\n    std::vector&lt;int&gt; vec2;\n    vec2.reserve(n);  \/\/ \u4e8b\u524d\u306b\u30e1\u30e2\u30ea\u3092\u78ba\u4fdd\n    for (int i = 0; i &lt; n; ++i) {\n        vec2.push_back(i);\n    }\n    auto end2 = std::chrono::high_resolution_clock::now();\n\n    \/\/ \u5b9f\u884c\u6642\u9593\u306e\u6bd4\u8f03\u3092\u8868\u793a\n    auto duration1 = std::chrono::duration_cast&lt;std::chrono::microseconds&gt;(end1 - start);\n    auto duration2 = std::chrono::duration_cast&lt;std::chrono::microseconds&gt;(end2 - start);\n    std::cout &lt;&lt; \"Without reserve: \" &lt;&lt; duration1.count() &lt;&lt; \"\u03bcs\\n\";\n    std::cout &lt;&lt; \"With reserve: \" &lt;&lt; duration2.count() &lt;&lt; \"\u03bcs\\n\";\n}<\/pre>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-10\">emplace_back()\u3067\u52b9\u7387\u7684\u306b\u8981\u7d20\u3092\u8ffd\u52a0\u3059\u308b<\/h3>\n\n\n\n<p>emplace_back()\u306f\u3001\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u3092\u76f4\u63a5\u69cb\u7bc9\u3059\u308b\u3053\u3068\u3067\u3001\u4e0d\u5fc5\u8981\u306a\u30b3\u30d4\u30fc\u3084\u79fb\u52d5\u3092\u907f\u3051\u308b\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">class ExpensiveObject {\npublic:\n    ExpensiveObject(int id, std::string name) \n        : id_(id), name_(std::move(name)) {}\n\nprivate:\n    int id_;\n    std::string name_;\n};\n\n\/\/ \u52b9\u7387\u7684\u306a\u8981\u7d20\u8ffd\u52a0\u306e\u6bd4\u8f03\nvoid compare_insertion_methods() {\n    std::vector&lt;ExpensiveObject&gt; vec1, vec2;\n\n    \/\/ push_back()\u306e\u5834\u5408\n    vec1.push_back(ExpensiveObject(1, \"test\"));  \/\/ \u4e00\u6642\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u306e\u751f\u6210\u304c\u5fc5\u8981\n\n    \/\/ emplace_back()\u306e\u5834\u5408\n    vec2.emplace_back(1, \"test\");  \/\/ \u76f4\u63a5\u69cb\u7bc9\u304c\u53ef\u80fd\n}<\/pre>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-11\">\u4e0d\u8981\u306a\u30b3\u30d4\u30fc\u3092\u9632\u3050\u30e0\u30fc\u30d6\u30bb\u30de\u30f3\u30c6\u30a3\u30af\u30b9\u306e\u6d3b\u7528<\/h3>\n\n\n\n<p>\u30e0\u30fc\u30d6\u30bb\u30de\u30f3\u30c6\u30a3\u30af\u30b9\u3092\u6d3b\u7528\u3059\u308b\u3053\u3068\u3067\u3001\u5927\u304d\u306a\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u306e\u4e0d\u8981\u306a\u30b3\u30d4\u30fc\u3092\u907f\u3051\u308b\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u52b9\u7387\u7684\u306a\u30c7\u30fc\u30bf\u8ee2\u9001<\/strong><\/li>\n<\/ol>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">std::vector&lt;std::string&gt; create_string_vector() {\n    std::vector&lt;std::string&gt; temp;\n    temp.reserve(3);\n    temp.emplace_back(\"Hello\");\n    temp.emplace_back(\"World\");\n    temp.emplace_back(\"!\");\n    return temp;  \/\/ RVO (Return Value Optimization)\u304c\u9069\u7528\u3055\u308c\u308b\n}\n\n\/\/ \u30e0\u30fc\u30d6\u306e\u6d3b\u7528\u4f8b\nvoid optimize_with_move() {\n    \/\/ \u30d9\u30af\u30bf\u30fc\u306e\u52b9\u7387\u7684\u306a\u79fb\u52d5\n    std::vector&lt;std::string&gt; vec1 = create_string_vector();\n    std::vector&lt;std::string&gt; vec2 = std::move(vec1);  \/\/ \u30c7\u30fc\u30bf\u306e\u6240\u6709\u6a29\u3092\u79fb\u52d5\n\n    \/\/ \u8981\u7d20\u306e\u52b9\u7387\u7684\u306a\u79fb\u52d5\n    std::string str = \"Large string data\";\n    vec2.push_back(std::move(str));  \/\/ str\u306e\u5185\u5bb9\u3092\u79fb\u52d5\n}<\/pre>\n\n\n\n<ol start=\"2\" class=\"wp-block-list\">\n<li><strong>\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u6700\u9069\u5316\u306e\u30d9\u30b9\u30c8\u30d7\u30e9\u30af\u30c6\u30a3\u30b9<\/strong><\/li>\n<\/ol>\n\n\n<div id=\"id-b9a24fc9-a632-4e77-aeaa-3647691ab78d\">\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><thead><tr><th>\u6700\u9069\u5316\u30c6\u30af\u30cb\u30c3\u30af<\/th><th>\u52b9\u679c<\/th><th>\u4f7f\u7528\u30b7\u30fc\u30f3<\/th><\/tr><\/thead><tbody><tr><td>reserve()<\/td><td>\u30e1\u30e2\u30ea\u518d\u5272\u308a\u5f53\u3066\u306e\u56de\u6570\u524a\u6e1b<\/td><td>\u30b5\u30a4\u30ba\u304c\u4e88\u6e2c\u53ef\u80fd\u306a\u5834\u5408<\/td><\/tr><tr><td>emplace_back()<\/td><td>\u30b3\u30f3\u30b9\u30c8\u30e9\u30af\u30b7\u30e7\u30f3\u306e\u6700\u9069\u5316<\/td><td>\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u306e\u76f4\u63a5\u69cb\u7bc9\u304c\u53ef\u80fd\u306a\u5834\u5408<\/td><\/tr><tr><td>\u30e0\u30fc\u30d6\u30bb\u30de\u30f3\u30c6\u30a3\u30af\u30b9<\/td><td>\u30b3\u30d4\u30fc\u30b3\u30b9\u30c8\u306e\u524a\u6e1b<\/td><td>\u5927\u304d\u306a\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u306e\u8ee2\u9001\u6642<\/td><\/tr><tr><td>shrink_to_fit()<\/td><td>\u30e1\u30e2\u30ea\u4f7f\u7528\u91cf\u306e\u6700\u9069\u5316<\/td><td>\u6700\u7d42\u30b5\u30a4\u30ba\u304c\u78ba\u5b9a\u3057\u305f\u5f8c<\/td><\/tr><\/tbody><\/table><\/figure>\n<\/div>\n\n\n<p>\u5b9f\u88c5\u6642\u306e\u91cd\u8981\u306a\u6ce8\u610f\u70b9\uff1a<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>reserve\u306f\u5fc5\u8981\u4ee5\u4e0a\u306b\u5927\u304d\u306a\u5024\u3092\u6307\u5b9a\u3057\u306a\u3044<\/li>\n\n\n\n<li>emplace_back\u4f7f\u7528\u6642\u306f\u578b\u306e\u5b8c\u5168\u8ee2\u9001\u306b\u6ce8\u610f<\/li>\n\n\n\n<li>\u30e0\u30fc\u30d6\u5f8c\u306e\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u306f\u672a\u5b9a\u7fa9\u72b6\u614b\u3068\u306a\u308b\u3053\u3068\u3092\u8003\u616e<\/li>\n\n\n\n<li>\u6700\u9069\u5316\u306b\u3088\u308b\u53ef\u8aad\u6027\u306e\u4f4e\u4e0b\u3068\u306e\u30c8\u30ec\u30fc\u30c9\u30aa\u30d5\u3092\u8003\u616e<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"i-12\">\u5b9f\u52d9\u3067\u3088\u304f\u3042\u308bvector\u306e\u6d3b\u7528\u30b7\u30fc\u30f3<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-13\">\u5927\u91cf\u30c7\u30fc\u30bf\u306e\u52b9\u7387\u7684\u306a\u51e6\u7406\u65b9\u6cd5<\/h3>\n\n\n\n<p>\u5b9f\u52d9\u3067\u306f\u5927\u91cf\u306e\u30c7\u30fc\u30bf\u3092\u52b9\u7387\u7684\u306b\u51e6\u7406\u3059\u308b\u5fc5\u8981\u304c\u3042\u308a\u307e\u3059\u3002\u4ee5\u4e0b\u306b\u4e00\u822c\u7684\u306a\u30b7\u30ca\u30ea\u30aa\u3068\u89e3\u6c7a\u65b9\u6cd5\u3092\u793a\u3057\u307e\u3059\u3002<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u30c7\u30fc\u30bf\u30d0\u30c3\u30c1\u51e6\u7406\u306e\u5b9f\u88c5<\/strong><\/li>\n<\/ol>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">class DataProcessor {\npublic:\n    \/\/ \u30d0\u30c3\u30c1\u30b5\u30a4\u30ba\u3092\u6307\u5b9a\u3057\u3066\u521d\u671f\u5316\n    DataProcessor(size_t batch_size) : batch_size_(batch_size) {\n        data_.reserve(batch_size);  \/\/ \u30e1\u30e2\u30ea\u3092\u4e8b\u524d\u78ba\u4fdd\n    }\n\n    \/\/ \u30c7\u30fc\u30bf\u306e\u8ffd\u52a0\u3068\u81ea\u52d5\u30d0\u30c3\u30c1\u51e6\u7406\n    void add_data(const Data&amp; item) {\n        data_.push_back(item);\n        if (data_.size() &gt;= batch_size_) {\n            process_batch();\n        }\n    }\n\nprivate:\n    void process_batch() {\n        \/\/ \u30d0\u30c3\u30c1\u51e6\u7406\u306e\u5b9f\u88c5\n        for (const auto&amp; item : data_) {\n            \/\/ \u5404\u30c7\u30fc\u30bf\u306e\u51e6\u7406\n        }\n        data_.clear();  \/\/ \u30d0\u30c3\u30c1\u3092\u30af\u30ea\u30a2\n        data_.reserve(batch_size_);  \/\/ \u6b21\u306e\u30d0\u30c3\u30c1\u306e\u305f\u3081\u306b\u30e1\u30e2\u30ea\u3092\u78ba\u4fdd\n    }\n\n    std::vector&lt;Data&gt; data_;\n    const size_t batch_size_;\n};<\/pre>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-14\">\u4e26\u5217\u51e6\u7406\u3067\u306e\u5b89\u5168\u306a\u4f7f\u7528\u6cd5<\/h3>\n\n\n\n<p>vector\u3092\u4e26\u5217\u51e6\u7406\u3067\u4f7f\u7528\u3059\u308b\u969b\u306f\u3001\u9069\u5207\u306a\u540c\u671f\u51e6\u7406\u304c\u91cd\u8981\u3067\u3059\u3002<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u30b9\u30ec\u30c3\u30c9\u30bb\u30fc\u30d5\u306a\u5b9f\u88c5\u4f8b<\/strong><\/li>\n<\/ol>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">#include &lt;mutex&gt;\n#include &lt;thread&gt;\n\nclass ThreadSafeVector {\npublic:\n    void add_item(const int&amp; item) {\n        std::lock_guard&lt;std::mutex&gt; lock(mutex_);\n        data_.push_back(item);\n    }\n\n    void process_parallel() {\n        std::vector&lt;std::thread&gt; threads;\n        const size_t num_threads = 4;\n\n        \/\/ \u30c7\u30fc\u30bf\u3092\u5206\u5272\u3057\u3066\u4e26\u5217\u51e6\u7406\n        for (size_t i = 0; i &lt; num_threads; ++i) {\n            threads.emplace_back([this, i, num_threads]() {\n                size_t start = (data_.size() * i) \/ num_threads;\n                size_t end = (data_.size() * (i + 1)) \/ num_threads;\n\n                for (size_t j = start; j &lt; end; ++j) {\n                    \/\/ \u5404\u8981\u7d20\u306e\u51e6\u7406\n                    process_item(data_[j]);\n                }\n            });\n        }\n\n        \/\/ \u3059\u3079\u3066\u306e\u30b9\u30ec\u30c3\u30c9\u306e\u5b8c\u4e86\u3092\u5f85\u6a5f\n        for (auto&amp; thread : threads) {\n            thread.join();\n        }\n    }\n\nprivate:\n    std::vector&lt;int&gt; data_;\n    std::mutex mutex_;\n\n    void process_item(int item) {\n        \/\/ \u500b\u5225\u306e\u8981\u7d20\u51e6\u7406\n    }\n};<\/pre>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-15\">\u30e1\u30e2\u30ea\u30ea\u30fc\u30af\u3092\u9632\u3050RAII\u30d1\u30bf\u30fc\u30f3\u306e\u5b9f\u88c5<\/h3>\n\n\n\n<p>RAII\u3092\u4f7f\u7528\u3057\u3066\u30ea\u30bd\u30fc\u30b9\u7ba1\u7406\u3092\u81ea\u52d5\u5316\u3059\u308b\u5b9f\u88c5\u4f8b\u3092\u793a\u3057\u307e\u3059\u3002<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">class ResourceManager {\npublic:\n    class Resource {\n    public:\n        Resource(int id) : id_(id) {\n            \/\/ \u30ea\u30bd\u30fc\u30b9\u306e\u521d\u671f\u5316\n        }\n        ~Resource() {\n            \/\/ \u30ea\u30bd\u30fc\u30b9\u306e\u89e3\u653e\n        }\n    private:\n        int id_;\n    };\n\n    void add_resource(int id) {\n        resources_.emplace_back(id);  \/\/ \u30ea\u30bd\u30fc\u30b9\u3092\u81ea\u52d5\u7ba1\u7406\n    }\n\n    \/\/ \u30ea\u30bd\u30fc\u30b9\u306e\u4f7f\u7528\n    void use_resources() {\n        for (const auto&amp; resource : resources_) {\n            \/\/ \u30ea\u30bd\u30fc\u30b9\u306e\u4f7f\u7528\n        }\n    }\n\nprivate:\n    std::vector&lt;Resource&gt; resources_;  \/\/ RAII\u306b\u3088\u308b\u81ea\u52d5\u7ba1\u7406\n};<\/pre>\n\n\n\n<p>\u5b9f\u52d9\u3067\u306e\u5b9f\u88c5\u30dd\u30a4\u30f3\u30c8\uff1a<\/p>\n\n\n<div id=\"id-44da3d8a-33b9-458d-aabc-e080c03a920c\">\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><thead><tr><th>\u30b7\u30ca\u30ea\u30aa<\/th><th>\u63a8\u5968\u3055\u308c\u308b\u5b9f\u88c5\u65b9\u6cd5<\/th><th>\u6ce8\u610f\u70b9<\/th><\/tr><\/thead><tbody><tr><td>\u5927\u91cf\u30c7\u30fc\u30bf\u51e6\u7406<\/td><td>\u30d0\u30c3\u30c1\u51e6\u7406\u306e\u5b9f\u88c5<\/td><td>\u30e1\u30e2\u30ea\u4f7f\u7528\u91cf\u306e\u76e3\u8996<\/td><\/tr><tr><td>\u4e26\u5217\u51e6\u7406<\/td><td>\u30df\u30e5\u30fc\u30c6\u30c3\u30af\u30b9\u306b\u3088\u308b\u4fdd\u8b77<\/td><td>\u30c7\u30c3\u30c9\u30ed\u30c3\u30af\u9632\u6b62<\/td><\/tr><tr><td>\u30ea\u30bd\u30fc\u30b9\u7ba1\u7406<\/td><td>RAII\u30d1\u30bf\u30fc\u30f3\u306e\u4f7f\u7528<\/td><td>\u4f8b\u5916\u5b89\u5168\u6027\u306e\u78ba\u4fdd<\/td><\/tr><\/tbody><\/table><\/figure>\n<\/div>\n\n\n<p>\u5b9f\u88c5\u6642\u306e\u91cd\u8981\u306a\u30dd\u30a4\u30f3\u30c8\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li>\u30c7\u30fc\u30bf\u6574\u5408\u6027\u306e\u78ba\u4fdd<\/li>\n<\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u4e26\u5217\u30a2\u30af\u30bb\u30b9\u6642\u306e\u540c\u671f\u51e6\u7406<\/li>\n\n\n\n<li>\u30c8\u30e9\u30f3\u30b6\u30af\u30b7\u30e7\u30f3\u7684\u306a\u51e6\u7406\u306e\u5b9f\u88c5<\/li>\n<\/ul>\n\n\n\n<ol class=\"wp-block-list\">\n<li>\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u306e\u6700\u9069\u5316<\/li>\n<\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u30d0\u30c3\u30c1\u30b5\u30a4\u30ba\u306e\u9069\u5207\u306a\u8a2d\u5b9a<\/li>\n\n\n\n<li>\u30e1\u30e2\u30ea\u518d\u5272\u308a\u5f53\u3066\u306e\u6700\u5c0f\u5316<\/li>\n<\/ul>\n\n\n\n<ol class=\"wp-block-list\">\n<li>\u30a8\u30e9\u30fc\u51e6\u7406<\/li>\n<\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u4f8b\u5916\u5b89\u5168\u306a\u5b9f\u88c5<\/li>\n\n\n\n<li>\u30a8\u30e9\u30fc\u72b6\u614b\u304b\u3089\u306e\u9069\u5207\u306a\u56de\u5fa9<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"i-16\">std::vector\u3092\u4f7f\u3046\u969b\u306e\u6ce8\u610f\u70b9\u3068\u56de\u907f\u7b56<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-17\">\u30a4\u30c6\u30ec\u30fc\u30bf\u7121\u52b9\u5316\u306e\u7f60\u3068\u5bfe\u51e6\u6cd5<\/h3>\n\n\n\n<p>vector\u306e\u30a4\u30c6\u30ec\u30fc\u30bf\u7121\u52b9\u5316\u306f\u3001\u591a\u304f\u306e\u30d0\u30b0\u306e\u539f\u56e0\u3068\u306a\u308b\u4ee3\u8868\u7684\u306a\u554f\u984c\u3067\u3059\u3002<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u30a4\u30c6\u30ec\u30fc\u30bf\u304c\u7121\u52b9\u5316\u3055\u308c\u308b\u30b1\u30fc\u30b9<\/strong><\/li>\n<\/ol>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">std::vector&lt;int&gt; vec = {1, 2, 3, 4, 5};\nauto it = vec.begin();  \/\/ \u30a4\u30c6\u30ec\u30fc\u30bf\u3092\u53d6\u5f97\n\n\/\/ \u4ee5\u4e0b\u306e\u64cd\u4f5c\u3067\u30a4\u30c6\u30ec\u30fc\u30bf\u304c\u7121\u52b9\u5316\u3055\u308c\u308b\nvec.push_back(6);      \/\/ \u30e1\u30e2\u30ea\u518d\u5272\u308a\u5f53\u3066\u306e\u53ef\u80fd\u6027\n\/\/ \u3053\u306e\u3042\u3068it\u4f7f\u7528\u3059\u308b\u3068\u672a\u5b9a\u7fa9\u52d5\u4f5c\n\n\/\/ \u6b63\u3057\u3044\u4f7f\u7528\u6cd5\nfor (auto it = vec.begin(); it != vec.end(); ) {\n    if (*it % 2 == 0) {\n        it = vec.erase(it);  \/\/ erase\u306f\u6b21\u306e\u6709\u52b9\u306a\u30a4\u30c6\u30ec\u30fc\u30bf\u3092\u8fd4\u3059\n    } else {\n        ++it;\n    }\n}<\/pre>\n\n\n\n<ol start=\"2\" class=\"wp-block-list\">\n<li><strong>\u5b89\u5168\u306a\u8981\u7d20\u524a\u9664\u30d1\u30bf\u30fc\u30f3<\/strong><\/li>\n<\/ol>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">class DataManager {\npublic:\n    void remove_if_condition(const std::function&lt;bool(const int&amp;)&gt;&amp; predicate) {\n        auto new_end = std::remove_if(data_.begin(), data_.end(), predicate);\n        data_.erase(new_end, data_.end());\n    }\n\nprivate:\n    std::vector&lt;int&gt; data_;\n};<\/pre>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-18\">\u30e1\u30e2\u30ea\u65ad\u7247\u5316\u3092\u9632\u3050\u30c6\u30af\u30cb\u30c3\u30af<\/h3>\n\n\n\n<p>\u30e1\u30e2\u30ea\u65ad\u7247\u5316\u306f\u3001\u9577\u671f\u5b9f\u884c\u30a2\u30d7\u30ea\u30b1\u30fc\u30b7\u30e7\u30f3\u3067\u306e\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u4f4e\u4e0b\u306e\u539f\u56e0\u3068\u306a\u308a\u307e\u3059\u3002<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u30e1\u30e2\u30ea\u30ec\u30a4\u30a2\u30a6\u30c8\u306e\u6700\u9069\u5316<\/strong><\/li>\n<\/ol>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">class OptimizedStorage {\npublic:\n    void optimize() {\n        \/\/ \u4e0d\u8981\u306a\u30ad\u30e3\u30d1\u30b7\u30c6\u30a3\u3092\u524a\u9664\n        std::vector&lt;Data&gt;(data_).swap(data_);\n\n        \/\/ \u307e\u305f\u306f\u4ee5\u4e0b\u306e\u65b9\u6cd5\u3082\u53ef\n        data_.shrink_to_fit();\n    }\n\n    void prepare_for_batch(size_t expected_size) {\n        \/\/ \u30d0\u30c3\u30c1\u51e6\u7406\u524d\u306b\u30e1\u30e2\u30ea\u3092\u6700\u9069\u5316\n        data_.reserve(data_.size() + expected_size);\n    }\n\nprivate:\n    std::vector&lt;Data&gt; data_;\n};<\/pre>\n\n\n\n<ol start=\"2\" class=\"wp-block-list\">\n<li><strong>\u30ab\u30b9\u30bf\u30e0\u30a2\u30ed\u30b1\u30fc\u30bf\u306e\u4f7f\u7528\u4f8b<\/strong><\/li>\n<\/ol>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">template&lt;typename T&gt;\nclass PoolAllocator {\npublic:\n    using value_type = T;\n\n    PoolAllocator() noexcept {}\n\n    T* allocate(std::size_t n) {\n        \/\/ \u30e1\u30e2\u30ea\u30d7\u30fc\u30eb\u304b\u3089\u306e\u5272\u308a\u5f53\u3066\n        return static_cast&lt;T*&gt;(pool_.allocate(n * sizeof(T)));\n    }\n\n    void deallocate(T* p, std::size_t n) noexcept {\n        pool_.deallocate(p, n * sizeof(T));\n    }\n\nprivate:\n    MemoryPool pool_;\n};\n\n\/\/ \u4f7f\u7528\u4f8b\nstd::vector&lt;int, PoolAllocator&lt;int&gt;&gt; optimized_vec;<\/pre>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-19\">\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u30dc\u30c8\u30eb\u30cd\u30c3\u30af\u306e\u7279\u5b9a\u3068\u89e3\u6c7a<\/h3>\n\n\n\n<p>\u4e00\u822c\u7684\u306a\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u554f\u984c\u3068\u305d\u306e\u89e3\u6c7a\u7b56\u3092\u793a\u3057\u307e\u3059\u3002<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u983b\u7e41\u306a\u30e1\u30e2\u30ea\u518d\u5272\u308a\u5f53\u3066\u306e\u691c\u51fa\u3068\u5bfe\u7b56<\/strong><\/li>\n<\/ol>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">class PerformanceMonitor {\npublic:\n    void monitor_allocations() {\n        std::vector&lt;int&gt; vec;\n        size_t last_capacity = vec.capacity();\n\n        for (int i = 0; i &lt; 1000; ++i) {\n            vec.push_back(i);\n\n            if (vec.capacity() != last_capacity) {\n                std::cout &lt;&lt; \"Reallocation at size: \" &lt;&lt; vec.size() \n                         &lt;&lt; \" New capacity: \" &lt;&lt; vec.capacity() &lt;&lt; std::endl;\n                last_capacity = vec.capacity();\n            }\n        }\n    }\n};<\/pre>\n\n\n\n<ol start=\"2\" class=\"wp-block-list\">\n<li><strong>\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u6700\u9069\u5316\u306e\u30c1\u30a7\u30c3\u30af\u30ea\u30b9\u30c8<\/strong><\/li>\n<\/ol>\n\n\n<div id=\"id-2bba7a90-ad03-49af-8be0-207de887274e\">\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><thead><tr><th>\u554f\u984c<\/th><th>\u75c7\u72b6<\/th><th>\u89e3\u6c7a\u7b56<\/th><\/tr><\/thead><tbody><tr><td>\u983b\u7e41\u306a\u518d\u5272\u308a\u5f53\u3066<\/td><td>\u30e1\u30e2\u30ea\u4f7f\u7528\u7387\u306e\u6025\u6fc0\u306a\u5909\u52d5<\/td><td>reserve()\u306e\u9069\u5207\u306a\u4f7f\u7528<\/td><\/tr><tr><td>\u30a4\u30c6\u30ec\u30fc\u30bf\u7121\u52b9\u5316<\/td><td>\u4e88\u671f\u305b\u306c\u30af\u30e9\u30c3\u30b7\u30e5<\/td><td>\u30a4\u30c6\u30ec\u30fc\u30bf\u306e\u5373\u6642\u66f4\u65b0<\/td><\/tr><tr><td>\u30e1\u30e2\u30ea\u65ad\u7247\u5316<\/td><td>\u9577\u671f\u5b9f\u884c\u6642\u306e\u30e1\u30e2\u30ea\u5897\u52a0<\/td><td>shrink_to_fit()\u306e\u5b9a\u671f\u5b9f\u884c<\/td><\/tr><tr><td>\u4e0d\u8981\u306a\u30b3\u30d4\u30fc<\/td><td>\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u4f4e\u4e0b<\/td><td>\u30e0\u30fc\u30d6\u30bb\u30de\u30f3\u30c6\u30a3\u30af\u30b9\u306e\u6d3b\u7528<\/td><\/tr><\/tbody><\/table><\/figure>\n<\/div>\n\n\n<p>\u5b9f\u88c5\u6642\u306e\u91cd\u8981\u306a\u6ce8\u610f\u70b9\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u4f8b\u5916\u5b89\u5168\u6027\u306e\u78ba\u4fdd<\/strong><\/li>\n<\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u5f37\u3044\u4f8b\u5916\u4fdd\u8a3c\u304c\u5fc5\u8981\u306a\u64cd\u4f5c\u306e\u7279\u5b9a<\/li>\n\n\n\n<li>\u30c8\u30e9\u30f3\u30b6\u30af\u30b7\u30e7\u30f3\u7684\u306a\u66f4\u65b0\u306e\u5b9f\u88c5<\/li>\n<\/ul>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u30ea\u30bd\u30fc\u30b9\u7ba1\u7406<\/strong><\/li>\n<\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u30e1\u30e2\u30ea\u30ea\u30fc\u30af\u306e\u9632\u6b62<\/li>\n\n\n\n<li>RAII\u30d1\u30bf\u30fc\u30f3\u306e\u9069\u5207\u306a\u4f7f\u7528<\/li>\n<\/ul>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u30c7\u30d0\u30c3\u30b0\u3068\u30d7\u30ed\u30d5\u30a1\u30a4\u30ea\u30f3\u30b0<\/strong><\/li>\n<\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u30db\u30c3\u30c8\u30b9\u30dd\u30c3\u30c8\u306e\u7279\u5b9a<\/li>\n\n\n\n<li>\u30e1\u30e2\u30ea\u4f7f\u7528\u72b6\u6cc1\u306e\u76e3\u8996<\/li>\n<\/ul>\n\n\n\n<p>\u3053\u308c\u3089\u306e\u6ce8\u610f\u70b9\u3092\u610f\u8b58\u3059\u308b\u3053\u3068\u3067\u3001\u3088\u308a\u5b89\u5168\u3067\u52b9\u7387\u7684\u306avector\u306e\u4f7f\u7528\u304c\u53ef\u80fd\u306b\u306a\u308a\u307e\u3059\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Warning: Undefined array key &#8220;is_admin&#8221; in \/home\/xs392991\/dexall.co.jp\/public_html\/articles\/wp-content\/themes\/ &#8230; <\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[5],"tags":[],"class_list":{"0":"post-1610","1":"post","2":"type-post","3":"status-publish","4":"format-standard","6":"category-cpp","7":"nothumb"},"_links":{"self":[{"href":"https:\/\/dexall.co.jp\/articles\/index.php?rest_route=\/wp\/v2\/posts\/1610","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/dexall.co.jp\/articles\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/dexall.co.jp\/articles\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/dexall.co.jp\/articles\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/dexall.co.jp\/articles\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1610"}],"version-history":[{"count":1,"href":"https:\/\/dexall.co.jp\/articles\/index.php?rest_route=\/wp\/v2\/posts\/1610\/revisions"}],"predecessor-version":[{"id":1611,"href":"https:\/\/dexall.co.jp\/articles\/index.php?rest_route=\/wp\/v2\/posts\/1610\/revisions\/1611"}],"wp:attachment":[{"href":"https:\/\/dexall.co.jp\/articles\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1610"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/dexall.co.jp\/articles\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1610"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/dexall.co.jp\/articles\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1610"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}