{"id":1712,"date":"2025-03-24T08:50:07","date_gmt":"2025-03-23T23:50:07","guid":{"rendered":"https:\/\/dexall.co.jp\/articles\/?p=1712"},"modified":"2025-03-24T08:50:07","modified_gmt":"2025-03-23T23:50:07","slug":"%e3%80%90%e5%ae%8c%e5%85%a8%e8%a7%a3%e8%aa%ac%e3%80%91c-substr%e3%81%ae%e4%bd%bf%e3%81%84%e6%96%b9%e3%81%a8%e3%83%99%e3%82%b9%e3%83%88%e3%83%97%e3%83%a9%e3%82%af%e3%83%86%e3%82%a3%e3%82%b92024","status":"publish","type":"post","link":"https:\/\/dexall.co.jp\/articles\/?p=1712","title":{"rendered":"\u3010\u5b8c\u5168\u89e3\u8aac\u3011C++ substr\u306e\u4f7f\u3044\u65b9\u3068\u30d9\u30b9\u30c8\u30d7\u30e9\u30af\u30c6\u30a3\u30b92024 &#8211; \u73fe\u5834\u3067\u4f7f\u3048\u308b\u5b9f\u8df5\u30c6\u30af\u30cb\u30c3\u30af\u96c6"},"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\">C++ substr\u3068\u306f\uff1f\u57fa\u672c\u304b\u3089\u5fdc\u7528\u307e\u3067\u5b8c\u5168\u89e3\u8aac<\/a>    <ul class=\"menu_level_1\">      <li class=\"first\">        <a href=\"#i-1\">\u6587\u5b57\u5217\u64cd\u4f5c\u306e\u57fa\u790e\u3068\u3057\u3066\u306esubstr\u95a2\u6570\u306e\u5f79\u5272<\/a>      <\/li>      <li class=\"last\">        <a href=\"#i-2\">std::string\u30af\u30e9\u30b9\u306b\u304a\u3051\u308bsubstr\u30e1\u30bd\u30c3\u30c9\u306e\u4f4d\u7f6e\u3065\u3051<\/a>      <\/li>    <\/ul>  <\/li>  <li>    <a href=\"#i-3\">substr\u306e\u57fa\u672c\u7684\u306a\u4f7f\u3044\u65b9\u3092\u30de\u30b9\u30bf\u30fc\u3057\u3088\u3046<\/a>    <ul class=\"menu_level_1\">      <li class=\"first\">        <a href=\"#i-4\">\u5f15\u6570\u306e\u610f\u5473\u3068\u4f7f\u3044\u65b9\u3092\u8a73\u3057\u304f\u7406\u89e3\u3059\u308b<\/a>      <\/li>      <li class=\"last\">        <a href=\"#i-5\">\u623b\u308a\u5024\u306e\u578b\u3068\u7279\u5fb4\u3092\u628a\u63e1\u3059\u308b<\/a>      <\/li>    <\/ul>  <\/li>  <li>    <a href=\"#i-6\">\u5b9f\u8df5\u7684\u306asubstr\u306e\u6d3b\u7528\u30c6\u30af\u30cb\u30c3\u30af<\/a>    <ul class=\"menu_level_1\">      <li class=\"first\">        <a href=\"#i-7\">\u6587\u5b57\u5217\u306e\u5206\u5272\u3068\u62bd\u51fa\u306e\u52b9\u7387\u7684\u306a\u5b9f\u88c5\u65b9\u6cd5<\/a>      <\/li>      <li class=\"last\">        <a href=\"#i-8\">\u5927\u898f\u6a21\u30c6\u30ad\u30b9\u30c8\u51e6\u7406\u3067\u306e\u6d3b\u7528\u8853<\/a>      <\/li>    <\/ul>  <\/li>  <li>    <a href=\"#i-9\">substr\u4f7f\u7528\u6642\u306e\u6ce8\u610f\u70b9\u3068\u5bfe\u7b56<\/a>    <ul class=\"menu_level_1\">      <li class=\"first\">        <a href=\"#i-10\">\u7bc4\u56f2\u5916\u30a2\u30af\u30bb\u30b9\u306e\u9632\u6b62\u3068\u30a8\u30e9\u30fc\u30cf\u30f3\u30c9\u30ea\u30f3\u30b0<\/a>      <\/li>      <li class=\"last\">        <a href=\"#i-11\">\u30e1\u30e2\u30ea\u52b9\u7387\u3092\u8003\u616e\u3057\u305f\u5b9f\u88c5\u65b9\u6cd5<\/a>      <\/li>    <\/ul>  <\/li>  <li>    <a href=\"#i-12\">\u73fe\u5834\u3067\u4f7f\u3048\u308bsubstr\u306e\u30d9\u30b9\u30c8\u30d7\u30e9\u30af\u30c6\u30a3\u30b9<\/a>    <ul class=\"menu_level_1\">      <li class=\"first\">        <a href=\"#i-13\">\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u3092\u610f\u8b58\u3057\u305f\u5b9f\u88c5\u30d1\u30bf\u30fc\u30f3<\/a>      <\/li>      <li class=\"last\">        <a href=\"#i-14\">\u53ef\u8aad\u6027\u3068\u30e1\u30f3\u30c6\u30ca\u30f3\u30b9\u6027\u306e\u9ad8\u3044\u30b3\u30fc\u30c9\u8a2d\u8a08<\/a>      <\/li>    <\/ul>  <\/li>  <li class=\"last\">    <a href=\"#i-15\">C++20\u4ee5\u964d\u3067\u306esubstr\u6d3b\u7528\u6cd5<\/a>    <ul class=\"menu_level_1\">      <li class=\"first\">        <a href=\"#i-16\">\u6700\u65b0\u6a19\u6e96\u306b\u304a\u3051\u308b\u6587\u5b57\u5217\u64cd\u4f5c\u306e\u63a8\u5968\u30d1\u30bf\u30fc\u30f3<\/a>      <\/li>      <li class=\"last\">        <a href=\"#i-17\">\u65b0\u6a5f\u80fd\u3068\u306e\u7d44\u307f\u5408\u308f\u305b\u306b\u3088\u308b\u52b9\u679c\u7684\u306a\u5b9f\u88c5<\/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\">C++ substr\u3068\u306f\uff1f\u57fa\u672c\u304b\u3089\u5fdc\u7528\u307e\u3067\u5b8c\u5168\u89e3\u8aac<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-1\">\u6587\u5b57\u5217\u64cd\u4f5c\u306e\u57fa\u790e\u3068\u3057\u3066\u306esubstr\u95a2\u6570\u306e\u5f79\u5272<\/h3>\n\n\n\n<p>C++\u306e<code>substr<\/code>\u95a2\u6570\u306f\u3001std::string \u30af\u30e9\u30b9\u306b\u5b9f\u88c5\u3055\u308c\u3066\u3044\u308b\u6587\u5b57\u5217\u64cd\u4f5c\u306e\u57fa\u672c\u6a5f\u80fd\u3067\u3059\u3002\u3053\u306e\u95a2\u6570\u3092\u4f7f\u7528\u3059\u308b\u3053\u3068\u3067\u3001\u6587\u5b57\u5217\u304b\u3089\u90e8\u5206\u6587\u5b57\u5217\uff08substring\uff09\u3092\u7c21\u5358\u306b\u62bd\u51fa\u3059\u308b\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<p>\u4e3b\u306a\u7279\u5fb4\uff1a<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u65e2\u5b58\u306e\u6587\u5b57\u5217\u304b\u3089\u6307\u5b9a\u3057\u305f\u7bc4\u56f2\u306e\u90e8\u5206\u6587\u5b57\u5217\u3092\u53d6\u5f97<\/li>\n\n\n\n<li>\u65b0\u3057\u3044\u6587\u5b57\u5217\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u3068\u3057\u3066\u7d50\u679c\u3092\u8fd4\u5374<\/li>\n\n\n\n<li>\u4f4d\u7f6e\u3068\u9577\u3055\u3092\u6307\u5b9a\u3057\u3066\u67d4\u8edf\u306a\u62bd\u51fa\u304c\u53ef\u80fd<\/li>\n<\/ul>\n\n\n\n<p>\u57fa\u672c\u7684\u306a\u69cb\u6587\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=\"\">string substr(size_t pos = 0, size_t len = npos) const;<\/pre>\n\n\n\n<ul class=\"wp-block-list\">\n<li><code>pos<\/code>: \u62bd\u51fa\u3092\u958b\u59cb\u3059\u308b\u4f4d\u7f6e\uff08\u30a4\u30f3\u30c7\u30c3\u30af\u30b9\uff09<\/li>\n\n\n\n<li><code>len<\/code>: \u62bd\u51fa\u3059\u308b\u6587\u5b57\u5217\u306e\u9577\u3055\uff08\u7701\u7565\u53ef\u80fd\uff09<\/li>\n\n\n\n<li>\u623b\u308a\u5024: \u62bd\u51fa\u3055\u308c\u305f\u65b0\u3057\u3044\u6587\u5b57\u5217\u30aa\u30d6\u30b8\u30a7\u30af\u30c8<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-2\">std::string\u30af\u30e9\u30b9\u306b\u304a\u3051\u308bsubstr\u30e1\u30bd\u30c3\u30c9\u306e\u4f4d\u7f6e\u3065\u3051<\/h3>\n\n\n\n<p><code>substr<\/code>\u306f\u3001std::string\u30af\u30e9\u30b9\u306e\u30e1\u30f3\u30d0\u95a2\u6570\u3068\u3057\u3066\u4ee5\u4e0b\u306e\u3088\u3046\u306a\u7279\u5fb4\u7684\u306a\u4f4d\u7f6e\u3065\u3051\u3092\u6301\u3063\u3066\u3044\u307e\u3059\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u975e\u7834\u58ca\u7684\u64cd\u4f5c<\/strong><\/li>\n<\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u5143\u306e\u6587\u5b57\u5217\u3092\u5909\u66f4\u305b\u305a\u3001\u65b0\u3057\u3044\u6587\u5b57\u5217\u3092\u751f\u6210<\/li>\n\n\n\n<li>\u5143\u306e\u30c7\u30fc\u30bf\u306e\u5b89\u5168\u6027\u3092\u4fdd\u8a3c<\/li>\n<\/ul>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>STL\u3068\u306e\u89aa\u548c\u6027<\/strong><\/li>\n<\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u30a4\u30c6\u30ec\u30fc\u30bf\u3084\u30a2\u30eb\u30b4\u30ea\u30ba\u30e0\u3068\u7d44\u307f\u5408\u308f\u305b\u3066\u4f7f\u7528\u53ef\u80fd<\/li>\n\n\n\n<li>\u4ed6\u306eSTL\u6587\u5b57\u5217\u64cd\u4f5c\u3068\u9023\u643a\u3057\u305f\u51e6\u7406\u304c\u5bb9\u6613<\/li>\n<\/ul>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u30e1\u30e2\u30ea\u7ba1\u7406\u306e\u7279\u5fb4<\/strong><\/li>\n<\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u65b0\u3057\u3044\u6587\u5b57\u5217\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u306e\u305f\u3081\u306e\u30e1\u30e2\u30ea\u78ba\u4fdd\u304c\u81ea\u52d5\u7684\u306b\u884c\u308f\u308c\u308b<\/li>\n\n\n\n<li>RAII\u539f\u5247\u306b\u5f93\u3063\u305f\u5b89\u5168\u306a\u30e1\u30e2\u30ea\u7ba1\u7406<\/li>\n<\/ul>\n\n\n\n<p>\u5b9f\u88c5\u4f8b\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=\"\">#include &lt;string&gt;\n#include &lt;iostream&gt;\n\nint main() {\n    std::string original = \"Hello, C++ World!\";\n\n    \/\/ \u57fa\u672c\u7684\u306a\u4f7f\u7528\u4f8b\n    std::string sub1 = original.substr(7, 3);  \/\/ \"C++\"\u3092\u62bd\u51fa\n\n    \/\/ \u7d42\u7aef\u307e\u3067\u306e\u62bd\u51fa\n    std::string sub2 = original.substr(7);     \/\/ \"C++ World!\"\u3092\u62bd\u51fa\n\n    \/\/ \u5148\u982d\u304b\u3089\u306e\u62bd\u51fa\n    std::string sub3 = original.substr(0, 5);  \/\/ \"Hello\"\u3092\u62bd\u51fa\n\n    std::cout &lt;&lt; \"Original: \" &lt;&lt; original &lt;&lt; std::endl;\n    std::cout &lt;&lt; \"sub1: \" &lt;&lt; sub1 &lt;&lt; std::endl;\n    std::cout &lt;&lt; \"sub2: \" &lt;&lt; sub2 &lt;&lt; std::endl;\n    std::cout &lt;&lt; \"sub3: \" &lt;&lt; sub3 &lt;&lt; std::endl;\n\n    return 0;\n}<\/pre>\n\n\n\n<p>\u3053\u306e\u30b3\u30fc\u30c9\u306e\u5b9f\u884c\u7d50\u679c\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=\"\">Original: Hello, C++ World!\nsub1: C++\nsub2: C++ World!\nsub3: Hello<\/pre>\n\n\n\n<p>\u6587\u5b57\u5217\u51e6\u7406\u306b\u304a\u3044\u3066\u3001<code>substr<\/code>\u306f\u4ee5\u4e0b\u306e\u3088\u3046\u306a\u5834\u9762\u3067\u7279\u306b\u91cd\u8981\u306a\u5f79\u5272\u3092\u679c\u305f\u3057\u307e\u3059\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li>\u30c6\u30ad\u30b9\u30c8\u30d1\u30fc\u30b9\u51e6\u7406<\/li>\n<\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u30d5\u30a1\u30a4\u30eb\u540d\u3084\u62e1\u5f35\u5b50\u306e\u62bd\u51fa<\/li>\n\n\n\n<li>URL\u3084\u30d1\u30b9\u306e\u89e3\u6790<\/li>\n\n\n\n<li>\u30c7\u30fc\u30bf\u306e\u5207\u308a\u51fa\u3057<\/li>\n<\/ul>\n\n\n\n<ol class=\"wp-block-list\">\n<li>\u6587\u5b57\u5217\u306e\u5206\u5272\u3068\u7d50\u5408<\/li>\n<\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u7279\u5b9a\u90e8\u5206\u306e\u62bd\u51fa\u3068\u65b0\u3057\u3044\u6587\u5b57\u5217\u306e\u751f\u6210<\/li>\n\n\n\n<li>\u6587\u5b57\u5217\u306e\u90e8\u5206\u7684\u306a\u7f6e\u63db\u3084\u4fee\u6b63<\/li>\n<\/ul>\n\n\n\n<ol class=\"wp-block-list\">\n<li>\u30c7\u30fc\u30bf\u52a0\u5de5\u51e6\u7406<\/li>\n<\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u30ed\u30b0\u89e3\u6790<\/li>\n\n\n\n<li>\u30c6\u30ad\u30b9\u30c8\u30d5\u30a3\u30eb\u30bf\u30ea\u30f3\u30b0<\/li>\n\n\n\n<li>\u30d5\u30a9\u30fc\u30de\u30c3\u30c8\u5909\u63db<\/li>\n<\/ul>\n\n\n\n<p>\u3053\u306e\u3088\u3046\u306b\u3001<code>substr<\/code>\u306f\u6587\u5b57\u5217\u64cd\u4f5c\u306e\u57fa\u672c\u7684\u306a\u69cb\u6210\u8981\u7d20\u3068\u3057\u3066\u3001\u591a\u304f\u306e\u6587\u5b57\u5217\u51e6\u7406\u30bf\u30b9\u30af\u306e\u57fa\u76e4\u3068\u306a\u3063\u3066\u3044\u307e\u3059\u3002\u6b21\u306e\u30bb\u30af\u30b7\u30e7\u30f3\u3067\u306f\u3001\u3088\u308a\u5177\u4f53\u7684\u306a\u4f7f\u7528\u65b9\u6cd5\u3068\u5b9f\u8df5\u7684\u306a\u6d3b\u7528\u65b9\u6cd5\u306b\u3064\u3044\u3066\u8aac\u660e\u3057\u3066\u3044\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"i-3\">substr\u306e\u57fa\u672c\u7684\u306a\u4f7f\u3044\u65b9\u3092\u30de\u30b9\u30bf\u30fc\u3057\u3088\u3046<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-4\">\u5f15\u6570\u306e\u610f\u5473\u3068\u4f7f\u3044\u65b9\u3092\u8a73\u3057\u304f\u7406\u89e3\u3059\u308b<\/h3>\n\n\n\n<p><code>substr<\/code>\u95a2\u6570\u306f2\u3064\u306e\u5f15\u6570\u3092\u53d6\u308a\u307e\u3059\u304c\u3001\u305d\u308c\u305e\u308c\u306e\u610f\u5473\u3068\u4f7f\u3044\u65b9\u3092\u6b63\u78ba\u306b\u7406\u89e3\u3059\u308b\u3053\u3068\u304c\u91cd\u8981\u3067\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=\"\">string substr(size_t pos = 0, size_t len = npos) const;<\/pre>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u7b2c\u4e00\u5f15\u6570 <code>pos<\/code>\uff08\u5fc5\u9808\uff09<\/strong><\/li>\n<\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u62bd\u51fa\u958b\u59cb\u4f4d\u7f6e\u3092\u6307\u5b9a<\/li>\n\n\n\n<li>0\u304b\u3089\u59cb\u307e\u308b\u30a4\u30f3\u30c7\u30c3\u30af\u30b9<\/li>\n\n\n\n<li>\u6587\u5b57\u5217\u306e\u9577\u3055\u4ee5\u4e0a\u306e\u5024\u3092\u6307\u5b9a\u3059\u308b\u3068<code>std::out_of_range<\/code>\u4f8b\u5916\u304c\u767a\u751f<\/li>\n<\/ul>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u7b2c\u4e8c\u5f15\u6570 <code>len<\/code>\uff08\u7701\u7565\u53ef\u80fd\uff09<\/strong><\/li>\n<\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u62bd\u51fa\u3059\u308b\u6587\u5b57\u5217\u306e\u9577\u3055\u3092\u6307\u5b9a<\/li>\n\n\n\n<li>\u7701\u7565\u6642\u306f\u6587\u5b57\u5217\u672b\u5c3e\u307e\u3067\u62bd\u51fa<\/li>\n\n\n\n<li><code>std::string::npos<\/code>\u3092\u6307\u5b9a\u3059\u308b\u3068\u6b8b\u308a\u306e\u5168\u6587\u5b57\u3092\u62bd\u51fa<\/li>\n\n\n\n<li>\u6b8b\u308a\u306e\u6587\u5b57\u6570\u3088\u308a\u5927\u304d\u306a\u5024\u3092\u6307\u5b9a\u3057\u305f\u5834\u5408\u3001\u672b\u5c3e\u307e\u3067\u304c\u62bd\u51fa\u3055\u308c\u308b<\/li>\n<\/ul>\n\n\n\n<p>\u5177\u4f53\u7684\u306a\u4f7f\u7528\u4f8b\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=\"\">#include &lt;string&gt;\n#include &lt;iostream&gt;\n\nint main() {\n    std::string text = \"Programming in C++\";\n\n    \/\/ \u57fa\u672c\u7684\u306a\u4f7f\u7528\u30d1\u30bf\u30fc\u30f3\n    std::string sub1 = text.substr(0, 11);     \/\/ \"Programming\"\u3092\u62bd\u51fa\n    std::string sub2 = text.substr(14);        \/\/ \"C++\"\u3092\u62bd\u51fa\n    std::string sub3 = text.substr(12, 2);     \/\/ \"in\"\u3092\u62bd\u51fa\n\n    \/\/ \u6587\u5b57\u5217\u672b\u5c3e\u307e\u3067\u306e\u62bd\u51fa\n    std::string sub4 = text.substr(0);         \/\/ \u5168\u6587\u5b57\u5217\u3092\u62bd\u51fa\n\n    \/\/ npos\u3092\u4f7f\u7528\u3057\u305f\u62bd\u51fa\n    std::string sub5 = text.substr(12, std::string::npos);  \/\/ \"in C++\"\u3092\u62bd\u51fa\n\n    \/\/ \u7d50\u679c\u306e\u8868\u793a\n    std::cout &lt;&lt; \"Original: \" &lt;&lt; text &lt;&lt; std::endl;\n    std::cout &lt;&lt; \"sub1: \" &lt;&lt; sub1 &lt;&lt; std::endl;\n    std::cout &lt;&lt; \"sub2: \" &lt;&lt; sub2 &lt;&lt; std::endl;\n    std::cout &lt;&lt; \"sub3: \" &lt;&lt; sub3 &lt;&lt; std::endl;\n    std::cout &lt;&lt; \"sub4: \" &lt;&lt; sub4 &lt;&lt; std::endl;\n    std::cout &lt;&lt; \"sub5: \" &lt;&lt; sub5 &lt;&lt; std::endl;\n\n    return 0;\n}<\/pre>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-5\">\u623b\u308a\u5024\u306e\u578b\u3068\u7279\u5fb4\u3092\u628a\u63e1\u3059\u308b<\/h3>\n\n\n\n<p><code>substr<\/code>\u95a2\u6570\u306e\u623b\u308a\u5024\u306b\u3064\u3044\u3066\u3001\u91cd\u8981\u306a\u7279\u5fb4\u3092\u7406\u89e3\u3057\u307e\u3057\u3087\u3046\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u623b\u308a\u5024\u306e\u578b<\/strong><\/li>\n<\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u65b0\u3057\u3044<code>std::string<\/code>\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u304c\u8fd4\u3055\u308c\u308b<\/li>\n\n\n\n<li>\u5143\u306e\u6587\u5b57\u5217\u306f\u5909\u66f4\u3055\u308c\u306a\u3044\uff08const \u30e1\u30f3\u30d0\u95a2\u6570\uff09<\/li>\n\n\n\n<li>\u30b3\u30d4\u30fc\u30b3\u30f3\u30b9\u30c8\u30e9\u30af\u30bf\u306b\u3088\u308b\u65b0\u3057\u3044\u30e1\u30e2\u30ea\u9818\u57df\u306e\u78ba\u4fdd<\/li>\n<\/ul>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u30e1\u30e2\u30ea\u7ba1\u7406\u306e\u7279\u5fb4<\/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;string&gt;\n   #include &lt;iostream&gt;\n\n   int main() {\n       std::string original = \"Hello, World!\";\n\n       \/\/ \u65b0\u3057\u3044\u30e1\u30e2\u30ea\u9818\u57df\u306b\u6587\u5b57\u5217\u304c\u30b3\u30d4\u30fc\u3055\u308c\u308b\n       std::string sub = original.substr(0, 5);\n\n       \/\/ \u5143\u306e\u6587\u5b57\u5217\u306f\u5909\u66f4\u3055\u308c\u306a\u3044\n       sub[0] = 'h';\n\n       std::cout &lt;&lt; \"Original: \" &lt;&lt; original &lt;&lt; std::endl;  \/\/ \"Hello, World!\"\n       std::cout &lt;&lt; \"Modified: \" &lt;&lt; sub &lt;&lt; std::endl;       \/\/ \"hello\"\n\n       return 0;\n   }<\/pre>\n\n\n\n<ol start=\"3\" class=\"wp-block-list\">\n<li><strong>\u4f8b\u5916\u51e6\u7406<\/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;string&gt;\n   #include &lt;iostream&gt;\n\n   int main() {\n       std::string text = \"Example\";\n\n       try {\n           \/\/ \u7bc4\u56f2\u5916\u30a2\u30af\u30bb\u30b9\u306e\u4f8b\n           std::string sub = text.substr(10);  \/\/ \u4f8b\u5916\u304c\u767a\u751f\n       } catch (const std::out_of_range&amp; e) {\n           std::cout &lt;&lt; \"Error: \" &lt;&lt; e.what() &lt;&lt; std::endl;\n       }\n\n       try {\n           \/\/ \u6b63\u5e38\u306a\u7bc4\u56f2\u3067\u306e\u4f7f\u7528\n           std::string sub = text.substr(0, 4);  \/\/ \"Exam\"\n           std::cout &lt;&lt; \"Substring: \" &lt;&lt; sub &lt;&lt; std::endl;\n       } catch (const std::out_of_range&amp; e) {\n           std::cout &lt;&lt; \"Error: \" &lt;&lt; e.what() &lt;&lt; std::endl;\n       }\n\n       return 0;\n   }<\/pre>\n\n\n\n<ol start=\"4\" class=\"wp-block-list\">\n<li><strong>\u623b\u308a\u5024\u306e\u5229\u7528\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=\"\">   #include &lt;string&gt;\n   #include &lt;iostream&gt;\n   #include &lt;vector&gt;\n\n   int main() {\n       std::string text = \"apple,banana,orange\";\n       std::vector&lt;std::string&gt; fruits;\n\n       size_t start = 0;\n       size_t end = text.find(',');\n\n       \/\/ \u623b\u308a\u5024\u3092\u76f4\u63a5\u5229\u7528\u3057\u305f\u6587\u5b57\u5217\u5206\u5272\n       while (end != std::string::npos) {\n           fruits.push_back(text.substr(start, end - start));\n           start = end + 1;\n           end = text.find(',', start);\n       }\n       fruits.push_back(text.substr(start));\n\n       \/\/ \u7d50\u679c\u306e\u8868\u793a\n       for (const auto&amp; fruit : fruits) {\n           std::cout &lt;&lt; fruit &lt;&lt; std::endl;\n       }\n\n       return 0;\n   }<\/pre>\n\n\n\n<p>\u3053\u308c\u3089\u306e\u57fa\u672c\u7684\u306a\u4f7f\u3044\u65b9\u3092\u7406\u89e3\u3059\u308b\u3053\u3068\u3067\u3001\u3088\u308a\u8907\u96d1\u306a\u6587\u5b57\u5217\u51e6\u7406\u30bf\u30b9\u30af\u306b\u3082\u5bfe\u5fdc\u3067\u304d\u308b\u3088\u3046\u306b\u306a\u308a\u307e\u3059\u3002\u6b21\u306e\u30bb\u30af\u30b7\u30e7\u30f3\u3067\u306f\u3001\u3088\u308a\u5b9f\u8df5\u7684\u306a\u6d3b\u7528\u30c6\u30af\u30cb\u30c3\u30af\u306b\u3064\u3044\u3066\u8aac\u660e\u3057\u3066\u3044\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"i-6\">\u5b9f\u8df5\u7684\u306asubstr\u306e\u6d3b\u7528\u30c6\u30af\u30cb\u30c3\u30af<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-7\">\u6587\u5b57\u5217\u306e\u5206\u5272\u3068\u62bd\u51fa\u306e\u52b9\u7387\u7684\u306a\u5b9f\u88c5\u65b9\u6cd5<\/h3>\n\n\n\n<p>\u6587\u5b57\u5217\u306e\u5206\u5272\u3068\u62bd\u51fa\u306f\u3001\u5b9f\u52d9\u3067\u983b\u7e41\u306b\u5fc5\u8981\u3068\u306a\u308b\u64cd\u4f5c\u3067\u3059\u3002\u4ee5\u4e0b\u306b\u3001\u52b9\u7387\u7684\u306a\u5b9f\u88c5\u30d1\u30bf\u30fc\u30f3\u3092\u793a\u3057\u307e\u3059\u3002<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u533a\u5207\u308a\u6587\u5b57\u306b\u3088\u308b\u6587\u5b57\u5217\u5206\u5272<\/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;string&gt;\n#include &lt;vector&gt;\n#include &lt;iostream&gt;\n\nstd::vector&lt;std::string&gt; split(const std::string&amp; str, char delimiter) {\n    std::vector&lt;std::string&gt; tokens;\n    size_t start = 0;\n    size_t end = str.find(delimiter);\n\n    \/\/ \u533a\u5207\u308a\u6587\u5b57\u304c\u898b\u3064\u304b\u308b\u9650\u308a\u7e70\u308a\u8fd4\u3057\n    while (end != std::string::npos) {\n        tokens.push_back(str.substr(start, end - start));\n        start = end + 1;\n        end = str.find(delimiter, start);\n    }\n\n    \/\/ \u6700\u5f8c\u306e\u90e8\u5206\u3092\u8ffd\u52a0\n    tokens.push_back(str.substr(start));\n    return tokens;\n}\n\n\/\/ \u4f7f\u7528\u4f8b\nint main() {\n    std::string csv = \"apple,banana,orange,grape\";\n    std::vector&lt;std::string&gt; fruits = split(csv, ',');\n\n    for (const auto&amp; fruit : fruits) {\n        std::cout &lt;&lt; fruit &lt;&lt; std::endl;\n    }\n    return 0;\n}<\/pre>\n\n\n\n<ol start=\"2\" class=\"wp-block-list\">\n<li><strong>\u56fa\u5b9a\u9577\u30d5\u30a9\u30fc\u30de\u30c3\u30c8\u306e\u89e3\u6790<\/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;string&gt;\n#include &lt;iostream&gt;\n\nstruct Record {\n    std::string id;        \/\/ \u5148\u982d6\u6587\u5b57\n    std::string name;      \/\/ \u6b21\u306e20\u6587\u5b57\n    std::string date;      \/\/ \u6b21\u306e8\u6587\u5b57\n    std::string status;    \/\/ \u6b8b\u308a\u306e\u6587\u5b57\n\n    static Record parse(const std::string&amp; line) {\n        Record record;\n        size_t pos = 0;\n\n        record.id = line.substr(pos, 6);\n        pos += 6;\n\n        record.name = line.substr(pos, 20);\n        pos += 20;\n\n        record.date = line.substr(pos, 8);\n        pos += 8;\n\n        record.status = line.substr(pos);\n\n        return record;\n    }\n};\n\n\/\/ \u4f7f\u7528\u4f8b\nint main() {\n    std::string data = \"ID1234John Doe             20240118Active  \";\n    Record record = Record::parse(data);\n\n    std::cout &lt;&lt; \"ID: \" &lt;&lt; record.id &lt;&lt; std::endl;\n    std::cout &lt;&lt; \"Name: \" &lt;&lt; record.name &lt;&lt; std::endl;\n    std::cout &lt;&lt; \"Date: \" &lt;&lt; record.date &lt;&lt; std::endl;\n    std::cout &lt;&lt; \"Status: \" &lt;&lt; record.status &lt;&lt; std::endl;\n\n    return 0;\n}<\/pre>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-8\">\u5927\u898f\u6a21\u30c6\u30ad\u30b9\u30c8\u51e6\u7406\u3067\u306e\u6d3b\u7528\u8853<\/h3>\n\n\n\n<p>\u5927\u898f\u6a21\u306a\u30c6\u30ad\u30b9\u30c8\u30c7\u30fc\u30bf\u3092\u51e6\u7406\u3059\u308b\u969b\u306e\u52b9\u7387\u7684\u306a\u5b9f\u88c5\u30d1\u30bf\u30fc\u30f3\u3092\u7d39\u4ecb\u3057\u307e\u3059\u3002<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u30b9\u30c8\u30ea\u30fc\u30e0\u51e6\u7406\u3068\u306e\u7d44\u307f\u5408\u308f\u305b<\/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;string&gt;\n#include &lt;fstream&gt;\n#include &lt;iostream&gt;\n\nvoid process_large_file(const std::string&amp; filename) {\n    std::ifstream file(filename);\n    std::string line;\n    const size_t PREFIX_LENGTH = 10;\n\n    while (std::getline(file, line)) {\n        \/\/ \u5404\u884c\u306e\u5148\u982d10\u6587\u5b57\u3092\u51e6\u7406\n        if (line.length() &gt;= PREFIX_LENGTH) {\n            std::string prefix = line.substr(0, PREFIX_LENGTH);\n            \/\/ prefix\u306b\u5bfe\u3059\u308b\u51e6\u7406\n            std::cout &lt;&lt; \"Processing: \" &lt;&lt; prefix &lt;&lt; std::endl;\n        }\n    }\n}<\/pre>\n\n\n\n<ol start=\"2\" class=\"wp-block-list\">\n<li><strong>\u30e1\u30e2\u30ea\u52b9\u7387\u3092\u8003\u616e\u3057\u305f\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=\"\">#include &lt;string&gt;\n#include &lt;vector&gt;\n#include &lt;iostream&gt;\n\nclass TextProcessor {\nprivate:\n    std::string buffer;\n    static const size_t CHUNK_SIZE = 1024;\n\npublic:\n    void process_chunks(const std::string&amp; text) {\n        size_t pos = 0;\n        while (pos &lt; text.length()) {\n            \/\/ \u30c1\u30e3\u30f3\u30af\u5358\u4f4d\u3067\u51e6\u7406\n            std::string chunk = text.substr(pos, CHUNK_SIZE);\n            process_single_chunk(chunk);\n            pos += CHUNK_SIZE;\n        }\n    }\n\nprivate:\n    void process_single_chunk(const std::string&amp; chunk) {\n        \/\/ \u30c1\u30e3\u30f3\u30af\u306e\u672b\u5c3e\u304c\u5358\u8a9e\u306e\u9014\u4e2d\u306e\u5834\u5408\n        size_t last_space = chunk.find_last_of(' ');\n        if (last_space != std::string::npos) {\n            \/\/ \u5b8c\u5168\u306a\u5358\u8a9e\u307e\u3067\u3092\u51e6\u7406\n            std::string complete_part = chunk.substr(0, last_space);\n            process_words(complete_part);\n\n            \/\/ \u6b8b\u308a\u3092\u6b21\u306e\u30c1\u30e3\u30f3\u30af\u306e\u305f\u3081\u306b\u30d0\u30c3\u30d5\u30a1\u306b\u4fdd\u5b58\n            buffer = chunk.substr(last_space + 1);\n        } else {\n            process_words(chunk);\n        }\n    }\n\n    void process_words(const std::string&amp; text) {\n        \/\/ \u5358\u8a9e\u5358\u4f4d\u306e\u51e6\u7406\u3092\u5b9f\u88c5\n        std::cout &lt;&lt; \"Processing: \" &lt;&lt; text &lt;&lt; std::endl;\n    }\n};\n\n\/\/ \u4f7f\u7528\u4f8b\nint main() {\n    TextProcessor processor;\n    std::string large_text = \"This is a very long text that needs to be processed efficiently...\";\n    processor.process_chunks(large_text);\n    return 0;\n}<\/pre>\n\n\n\n<ol start=\"3\" class=\"wp-block-list\">\n<li><strong>\u4e26\u5217\u51e6\u7406\u3067\u306e\u6d3b\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=\"\">#include &lt;string&gt;\n#include &lt;vector&gt;\n#include &lt;thread&gt;\n#include &lt;mutex&gt;\n#include &lt;iostream&gt;\n\nclass ParallelTextProcessor {\nprivate:\n    std::mutex mtx;\n    std::vector&lt;std::string&gt; results;\n\npublic:\n    void process_parallel(const std::string&amp; text, size_t num_threads) {\n        std::vector&lt;std::thread&gt; threads;\n        size_t chunk_size = text.length() \/ num_threads;\n\n        for (size_t i = 0; i &lt; num_threads; ++i) {\n            size_t start = i * chunk_size;\n            size_t length = (i == num_threads - 1) ? \n                           text.length() - start : chunk_size;\n\n            threads.emplace_back([this, &amp;text, start, length]() {\n                std::string chunk = text.substr(start, length);\n                process_chunk(chunk);\n            });\n        }\n\n        for (auto&amp; thread : threads) {\n            thread.join();\n        }\n    }\n\nprivate:\n    void process_chunk(const std::string&amp; chunk) {\n        \/\/ \u30c1\u30e3\u30f3\u30af\u306e\u51e6\u7406\n        std::string result = \"Processed: \" + chunk;\n\n        \/\/ \u7d50\u679c\u306e\u4fdd\u5b58\n        std::lock_guard&lt;std::mutex&gt; lock(mtx);\n        results.push_back(result);\n    }\n};<\/pre>\n\n\n\n<p>\u3053\u308c\u3089\u306e\u5b9f\u88c5\u30d1\u30bf\u30fc\u30f3\u3092\u7d44\u307f\u5408\u308f\u305b\u308b\u3053\u3068\u3067\u3001\u52b9\u7387\u7684\u3067\u5805\u7262\u306a\u6587\u5b57\u5217\u51e6\u7406\u30b7\u30b9\u30c6\u30e0\u3092\u69cb\u7bc9\u3059\u308b\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002\u6b21\u306e\u30bb\u30af\u30b7\u30e7\u30f3\u3067\u306f\u3001substr\u4f7f\u7528\u6642\u306e\u6ce8\u610f\u70b9\u3068\u5bfe\u7b56\u306b\u3064\u3044\u3066\u8aac\u660e\u3057\u3066\u3044\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"i-9\">substr\u4f7f\u7528\u6642\u306e\u6ce8\u610f\u70b9\u3068\u5bfe\u7b56<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-10\">\u7bc4\u56f2\u5916\u30a2\u30af\u30bb\u30b9\u306e\u9632\u6b62\u3068\u30a8\u30e9\u30fc\u30cf\u30f3\u30c9\u30ea\u30f3\u30b0<\/h3>\n\n\n\n<p>substr\u3092\u4f7f\u7528\u3059\u308b\u969b\u306e\u4e3b\u306a\u6ce8\u610f\u70b9\u3068\u3001\u305d\u308c\u3089\u306b\u5bfe\u3059\u308b\u9069\u5207\u306a\u5bfe\u51e6\u65b9\u6cd5\u3092\u89e3\u8aac\u3057\u307e\u3059\u3002<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u7bc4\u56f2\u5916\u30a2\u30af\u30bb\u30b9\u306e\u9632\u6b62<\/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;string&gt;\n#include &lt;iostream&gt;\n#include &lt;stdexcept&gt;\n\nclass SafeSubstring {\npublic:\n    static std::string extract(const std::string&amp; str, size_t pos, size_t len = std::string::npos) {\n        try {\n            \/\/ \u6587\u5b57\u5217\u9577\u306e\u30c1\u30a7\u30c3\u30af\n            if (pos &gt; str.length()) {\n                throw std::out_of_range(\"Position out of range\");\n            }\n\n            \/\/ \u5b9f\u969b\u306b\u62bd\u51fa\u53ef\u80fd\u306a\u9577\u3055\u306e\u8a08\u7b97\n            size_t available_len = str.length() - pos;\n            size_t actual_len = (len == std::string::npos) ? available_len : \n                                std::min(len, available_len);\n\n            return str.substr(pos, actual_len);\n        } catch (const std::out_of_range&amp; e) {\n            std::cerr &lt;&lt; \"Error: \" &lt;&lt; e.what() &lt;&lt; std::endl;\n            return \"\";  \/\/ \u30a8\u30e9\u30fc\u6642\u306f\u7a7a\u6587\u5b57\u5217\u3092\u8fd4\u3059\n        }\n    }\n};\n\n\/\/ \u4f7f\u7528\u4f8b\nint main() {\n    std::string text = \"Hello, World!\";\n\n    \/\/ \u5b89\u5168\u306a\u62bd\u51fa\n    std::cout &lt;&lt; SafeSubstring::extract(text, 7) &lt;&lt; std::endl;  \/\/ \"World!\"\n    std::cout &lt;&lt; SafeSubstring::extract(text, 20) &lt;&lt; std::endl; \/\/ \"\"\uff08\u30a8\u30e9\u30fc\uff09\n\n    return 0;\n}<\/pre>\n\n\n\n<ol start=\"2\" class=\"wp-block-list\">\n<li><strong>\u4f8b\u5916\u51e6\u7406\u306e\u30d9\u30b9\u30c8\u30d7\u30e9\u30af\u30c6\u30a3\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=\"\">#include &lt;string&gt;\n#include &lt;iostream&gt;\n#include &lt;optional&gt;\n\nclass StringExtractor {\npublic:\n    static std::optional&lt;std::string&gt; tryExtract(\n        const std::string&amp; str, size_t pos, size_t len = std::string::npos) {\n\n        if (pos &gt;= str.length()) {\n            return std::nullopt;\n        }\n\n        try {\n            return str.substr(pos, len);\n        } catch (const std::exception&amp; e) {\n            return std::nullopt;\n        }\n    }\n};\n\n\/\/ \u4f7f\u7528\u4f8b\nvoid processString(const std::string&amp; input) {\n    auto result = StringExtractor::tryExtract(input, 5, 3);\n    if (result) {\n        std::cout &lt;&lt; \"Extracted: \" &lt;&lt; *result &lt;&lt; std::endl;\n    } else {\n        std::cout &lt;&lt; \"Extraction failed\" &lt;&lt; std::endl;\n    }\n}<\/pre>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-11\">\u30e1\u30e2\u30ea\u52b9\u7387\u3092\u8003\u616e\u3057\u305f\u5b9f\u88c5\u65b9\u6cd5<\/h3>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u4e0d\u5fc5\u8981\u306a\u30b3\u30d4\u30fc\u306e\u56de\u907f<\/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;string&gt;\n#include &lt;string_view&gt;\n#include &lt;iostream&gt;\n\nclass EfficientSubstring {\npublic:\n    \/\/ string_view\u3092\u4f7f\u7528\u3057\u305f\u52b9\u7387\u7684\u306a\u5b9f\u88c5\n    static std::string_view getView(const std::string&amp; str, size_t pos, size_t len = std::string::npos) {\n        if (pos &gt;= str.length()) {\n            return std::string_view();\n        }\n\n        size_t actual_len = (len == std::string::npos) ? \n            str.length() - pos : std::min(len, str.length() - pos);\n\n        return std::string_view(str.data() + pos, actual_len);\n    }\n\n    \/\/ \u5fc5\u8981\u306a\u5834\u5408\u306e\u307f\u30b3\u30d4\u30fc\u3092\u4f5c\u6210\n    static std::string getCopy(const std::string&amp; str, size_t pos, size_t len = std::string::npos) {\n        auto view = getView(str, pos, len);\n        return std::string(view);\n    }\n};\n\n\/\/ \u30e1\u30e2\u30ea\u4f7f\u7528\u91cf\u306e\u6bd4\u8f03\nvoid compareMemoryUsage() {\n    std::string large_text(1000000, 'a');  \/\/ 100\u4e07\u6587\u5b57\u306e\u6587\u5b57\u5217\n\n    \/\/ \u901a\u5e38\u306esubstr\uff08\u30b3\u30d4\u30fc\u304c\u767a\u751f\uff09\n    auto substring1 = large_text.substr(0, 1000);\n\n    \/\/ string_view\u3092\u4f7f\u7528\uff08\u30b3\u30d4\u30fc\u306a\u3057\uff09\n    auto substring2 = EfficientSubstring::getView(large_text, 0, 1000);\n\n    std::cout &lt;&lt; \"Substr size: \" &lt;&lt; substring1.size() &lt;&lt; std::endl;\n    std::cout &lt;&lt; \"View size: \" &lt;&lt; substring2.size() &lt;&lt; std::endl;\n}<\/pre>\n\n\n\n<ol start=\"2\" class=\"wp-block-list\">\n<li><strong>\u30e1\u30e2\u30ea\u89e3\u653e\u306e\u30bf\u30a4\u30df\u30f3\u30b0\u5236\u5fa1<\/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;string&gt;\n#include &lt;memory&gt;\n#include &lt;iostream&gt;\n\nclass StringBuffer {\nprivate:\n    std::string data;\n    std::vector&lt;std::string_view&gt; views;\n\npublic:\n    void append(const std::string&amp; str) {\n        size_t pos = data.length();\n        data += str;\n\n        \/\/ \u6587\u5b57\u5217\u3078\u306e\u53c2\u7167\u3092\u4fdd\u6301\n        views.push_back(std::string_view(\n            data.data() + pos, str.length()\n        ));\n    }\n\n    void process() {\n        for (const auto&amp; view : views) {\n            \/\/ string_view\u3092\u4f7f\u7528\u3057\u305f\u51e6\u7406\n            std::cout &lt;&lt; \"Processing: \" &lt;&lt; view &lt;&lt; std::endl;\n        }\n\n        \/\/ \u5fc5\u8981\u306b\u5fdc\u3058\u3066\u30e1\u30e2\u30ea\u3092\u89e3\u653e\n        clear();\n    }\n\n    void clear() {\n        views.clear();\n        data.clear();\n        data.shrink_to_fit();\n    }\n};<\/pre>\n\n\n\n<ol start=\"3\" class=\"wp-block-list\">\n<li><strong>\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u6700\u9069\u5316\u306e\u305f\u3081\u306e\u30c1\u30a7\u30c3\u30af\u30ea\u30b9\u30c8<\/strong><\/li>\n<\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li>[x] \u6587\u5b57\u5217\u306e\u9577\u3055\u3092\u4e8b\u524d\u306b\u30c1\u30a7\u30c3\u30af<\/li>\n\n\n\n<li>[x] \u5fc5\u8981\u306a\u5834\u5408\u306e\u307f\u30b3\u30d4\u30fc\u3092\u4f5c\u6210<\/li>\n\n\n\n<li>[x] string_view\u306e\u6d3b\u7528<\/li>\n\n\n\n<li>[x] \u4f8b\u5916\u51e6\u7406\u306e\u9069\u5207\u306a\u5b9f\u88c5<\/li>\n\n\n\n<li>[x] \u30e1\u30e2\u30ea\u89e3\u653e\u306e\u30bf\u30a4\u30df\u30f3\u30b0\u7ba1\u7406<\/li>\n\n\n\n<li>[x] \u5927\u304d\u306a\u6587\u5b57\u5217\u306e\u52b9\u7387\u7684\u306a\u51e6\u7406<\/li>\n<\/ul>\n\n\n\n<p>\u3053\u308c\u3089\u306e\u6ce8\u610f\u70b9\u3068\u5bfe\u7b56\u3092\u9069\u5207\u306b\u5b9f\u88c5\u3059\u308b\u3053\u3068\u3067\u3001\u3088\u308a\u5b89\u5168\u3067\u52b9\u7387\u7684\u306a\u6587\u5b57\u5217\u51e6\u7406\u3092\u5b9f\u73fe\u3067\u304d\u307e\u3059\u3002\u6b21\u306e\u30bb\u30af\u30b7\u30e7\u30f3\u3067\u306f\u3001\u5b9f\u52d9\u3067\u306e\u5177\u4f53\u7684\u306a\u30d9\u30b9\u30c8\u30d7\u30e9\u30af\u30c6\u30a3\u30b9\u306b\u3064\u3044\u3066\u8aac\u660e\u3057\u3066\u3044\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"i-12\">\u73fe\u5834\u3067\u4f7f\u3048\u308bsubstr\u306e\u30d9\u30b9\u30c8\u30d7\u30e9\u30af\u30c6\u30a3\u30b9<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-13\">\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u3092\u610f\u8b58\u3057\u305f\u5b9f\u88c5\u30d1\u30bf\u30fc\u30f3<\/h3>\n\n\n\n<p>\u5b9f\u52d9\u3067\u3088\u304f\u906d\u9047\u3059\u308b\u72b6\u6cc1\u3067\u306e\u6700\u9069\u306a\u5b9f\u88c5\u30d1\u30bf\u30fc\u30f3\u3092\u7d39\u4ecb\u3057\u307e\u3059\u3002<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u6587\u5b57\u5217\u51e6\u7406\u30e6\u30fc\u30c6\u30a3\u30ea\u30c6\u30a3\u30af\u30e9\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=\"\">#include &lt;string&gt;\n#include &lt;string_view&gt;\n#include &lt;vector&gt;\n#include &lt;optional&gt;\n\nclass StringUtils {\npublic:\n    \/\/ \u5b89\u5168\u3067\u52b9\u7387\u7684\u306a\u90e8\u5206\u6587\u5b57\u5217\u62bd\u51fa\n    static std::optional&lt;std::string_view&gt; safeSubstring(\n        const std::string&amp; str,\n        size_t start,\n        size_t length = std::string::npos\n    ) {\n        if (start &gt;= str.length()) {\n            return std::nullopt;\n        }\n\n        size_t actual_length = (length == std::string::npos) ?\n            str.length() - start : std::min(length, str.length() - start);\n\n        return std::string_view(str.data() + start, actual_length);\n    }\n\n    \/\/ \u6587\u5b57\u5217\u5206\u5272\u306e\u6700\u9069\u5316\u5b9f\u88c5\n    static std::vector&lt;std::string_view&gt; split(\n        const std::string&amp; str,\n        char delimiter\n    ) {\n        std::vector&lt;std::string_view&gt; result;\n        size_t start = 0;\n\n        \/\/ \u4e88\u7d04\u306b\u3088\u308b\u30e1\u30e2\u30ea\u518d\u5272\u308a\u5f53\u3066\u306e\u524a\u6e1b\n        result.reserve(std::count(str.begin(), str.end(), delimiter) + 1);\n\n        while (start &lt; str.length()) {\n            size_t end = str.find(delimiter, start);\n            if (end == std::string::npos) {\n                result.push_back(std::string_view(str.data() + start, str.length() - start));\n                break;\n            }\n            result.push_back(std::string_view(str.data() + start, end - start));\n            start = end + 1;\n        }\n\n        return result;\n    }\n\n    \/\/ \u56fa\u5b9a\u9577\u30d5\u30a3\u30fc\u30eb\u30c9\u306e\u52b9\u7387\u7684\u306a\u62bd\u51fa\n    template&lt;typename T&gt;\n    static T extractField(\n        const std::string&amp; str,\n        size_t start,\n        size_t length,\n        const std::function&lt;T(std::string_view)&gt;&amp; converter\n    ) {\n        auto field = safeSubstring(str, start, length);\n        if (!field) {\n            throw std::out_of_range(\"Field extraction failed\");\n        }\n        return converter(*field);\n    }\n};\n\n\/\/ \u4f7f\u7528\u4f8b\nvoid demonstrate_string_utils() {\n    std::string data = \"12345John Doe           Active\";\n\n    \/\/ \u5b89\u5168\u306a\u90e8\u5206\u6587\u5b57\u5217\u62bd\u51fa\n    auto id = StringUtils::safeSubstring(data, 0, 5);\n    if (id) {\n        std::cout &lt;&lt; \"ID: \" &lt;&lt; *id &lt;&lt; std::endl;\n    }\n\n    \/\/ \u30ab\u30b9\u30bf\u30e0\u578b\u3078\u306e\u5909\u63db\n    auto numeric_id = StringUtils::extractField&lt;int&gt;(\n        data, 0, 5,\n        [](std::string_view sv) { return std::stoi(std::string(sv)); }\n    );\n}<\/pre>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-14\">\u53ef\u8aad\u6027\u3068\u30e1\u30f3\u30c6\u30ca\u30f3\u30b9\u6027\u306e\u9ad8\u3044\u30b3\u30fc\u30c9\u8a2d\u8a08<\/h3>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u8a2d\u5b9a\u99c6\u52d5\u306e\u6587\u5b57\u5217\u51e6\u7406<\/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;string&gt;\n#include &lt;unordered_map&gt;\n#include &lt;functional&gt;\n\nclass StringProcessor {\npublic:\n    \/\/ \u51e6\u7406\u30eb\u30fc\u30eb\u306e\u5b9a\u7fa9\n    struct ProcessingRule {\n        size_t start;\n        size_t length;\n        std::function&lt;void(std::string_view)&gt; processor;\n    };\n\nprivate:\n    std::unordered_map&lt;std::string, ProcessingRule&gt; rules;\n\npublic:\n    \/\/ \u30eb\u30fc\u30eb\u306e\u8ffd\u52a0\n    void addRule(\n        const std::string&amp; field_name,\n        size_t start,\n        size_t length,\n        std::function&lt;void(std::string_view)&gt; processor\n    ) {\n        rules[field_name] = {start, length, processor};\n    }\n\n    \/\/ \u6587\u5b57\u5217\u306e\u51e6\u7406\n    void processString(const std::string&amp; input) {\n        for (const auto&amp; [field_name, rule] : rules) {\n            if (auto field = StringUtils::safeSubstring(input, rule.start, rule.length)) {\n                rule.processor(*field);\n            }\n        }\n    }\n};\n\n\/\/ \u4f7f\u7528\u4f8b\nvoid process_structured_data() {\n    StringProcessor processor;\n\n    \/\/ \u30eb\u30fc\u30eb\u306e\u8a2d\u5b9a\n    processor.addRule(\"id\", 0, 5,\n        [](std::string_view sv) { std::cout &lt;&lt; \"ID: \" &lt;&lt; sv &lt;&lt; std::endl; });\n\n    processor.addRule(\"name\", 5, 20,\n        [](std::string_view sv) { std::cout &lt;&lt; \"Name: \" &lt;&lt; sv &lt;&lt; std::endl; });\n\n    \/\/ \u30c7\u30fc\u30bf\u51e6\u7406\n    processor.processString(\"12345John Doe           Active\");\n}<\/pre>\n\n\n\n<ol start=\"2\" class=\"wp-block-list\">\n<li><strong>\u30c6\u30b9\u30c8\u5bb9\u6613\u6027\u3092\u8003\u616e\u3057\u305f\u8a2d\u8a08<\/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;string&gt;\n#include &lt;cassert&gt;\n\nclass SubstringExtractor {\npublic:\n    virtual ~SubstringExtractor() = default;\n\n    virtual std::optional&lt;std::string_view&gt; extract(\n        const std::string&amp; str,\n        size_t start,\n        size_t length = std::string::npos\n    ) const {\n        return StringUtils::safeSubstring(str, start, length);\n    }\n};\n\nclass MockSubstringExtractor : public SubstringExtractor {\npublic:\n    std::optional&lt;std::string_view&gt; extract(\n        const std::string&amp; str,\n        size_t start,\n        size_t length = std::string::npos\n    ) const override {\n        \/\/ \u30c6\u30b9\u30c8\u7528\u306e\u5b9f\u88c5\n        return std::string_view(\"mock_result\");\n    }\n};\n\n\/\/ \u30c6\u30b9\u30c8\u30b1\u30fc\u30b9\nvoid test_substring_extraction() {\n    SubstringExtractor extractor;\n    std::string test_str = \"Hello, World!\";\n\n    \/\/ \u6b63\u5e38\u7cfb\u30c6\u30b9\u30c8\n    auto result1 = extractor.extract(test_str, 0, 5);\n    assert(result1 &amp;&amp; *result1 == \"Hello\");\n\n    \/\/ \u5883\u754c\u5024\u30c6\u30b9\u30c8\n    auto result2 = extractor.extract(test_str, test_str.length());\n    assert(!result2);\n\n    \/\/ \u30e2\u30c3\u30af\u3092\u4f7f\u7528\u3057\u305f\u30c6\u30b9\u30c8\n    MockSubstringExtractor mock_extractor;\n    auto result3 = mock_extractor.extract(test_str, 0, 5);\n    assert(result3 &amp;&amp; *result3 == \"mock_result\");\n}<\/pre>\n\n\n\n<ol start=\"3\" class=\"wp-block-list\">\n<li><strong>\u30d7\u30ed\u30c0\u30af\u30b7\u30e7\u30f3\u30ec\u30c7\u30a3\u306a\u30a8\u30e9\u30fc\u30cf\u30f3\u30c9\u30ea\u30f3\u30b0<\/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;string&gt;\n#include &lt;exception&gt;\n#include &lt;sstream&gt;\n\nclass SubstringError : public std::runtime_error {\npublic:\n    SubstringError(const std::string&amp; message) : std::runtime_error(message) {}\n};\n\nclass ProductionStringProcessor {\npublic:\n    static std::string process(const std::string&amp; input, size_t start, size_t length) {\n        try {\n            if (auto result = StringUtils::safeSubstring(input, start, length)) {\n                return std::string(*result);\n            }\n\n            std::stringstream ss;\n            ss &lt;&lt; \"Invalid substring parameters: start=\" &lt;&lt; start\n               &lt;&lt; \", length=\" &lt;&lt; length\n               &lt;&lt; \", string_length=\" &lt;&lt; input.length();\n            throw SubstringError(ss.str());\n\n        } catch (const std::exception&amp; e) {\n            \/\/ \u30a8\u30e9\u30fc\u30ed\u30b0\u306e\u8a18\u9332\n            logError(e.what());\n            \/\/ \u9069\u5207\u306a\u30d5\u30a9\u30fc\u30eb\u30d0\u30c3\u30af\u5024\u306e\u8fd4\u5374\n            return \"\";\n        }\n    }\n\nprivate:\n    static void logError(const std::string&amp; message) {\n        \/\/ \u30a8\u30e9\u30fc\u30ed\u30b0\u306e\u5b9f\u88c5\n        std::cerr &lt;&lt; \"Error: \" &lt;&lt; message &lt;&lt; std::endl;\n    }\n};<\/pre>\n\n\n\n<p>\u3053\u308c\u3089\u306e\u30d9\u30b9\u30c8\u30d7\u30e9\u30af\u30c6\u30a3\u30b9\u3092\u9069\u5207\u306b\u7d44\u307f\u5408\u308f\u305b\u308b\u3053\u3068\u3067\u3001\u4fdd\u5b88\u6027\u304c\u9ad8\u304f\u3001\u4fe1\u983c\u6027\u306e\u3042\u308b\u6587\u5b57\u5217\u51e6\u7406\u30b7\u30b9\u30c6\u30e0\u3092\u69cb\u7bc9\u3067\u304d\u307e\u3059\u3002\u6b21\u306e\u30bb\u30af\u30b7\u30e7\u30f3\u3067\u306f\u3001C++20\u4ee5\u964d\u3067\u306e\u65b0\u3057\u3044\u6d3b\u7528\u65b9\u6cd5\u306b\u3064\u3044\u3066\u8aac\u660e\u3057\u3066\u3044\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"i-15\">C++20\u4ee5\u964d\u3067\u306esubstr\u6d3b\u7528\u6cd5<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-16\">\u6700\u65b0\u6a19\u6e96\u306b\u304a\u3051\u308b\u6587\u5b57\u5217\u64cd\u4f5c\u306e\u63a8\u5968\u30d1\u30bf\u30fc\u30f3<\/h3>\n\n\n\n<p>C++20\u4ee5\u964d\u3067\u5c0e\u5165\u3055\u308c\u305f\u65b0\u6a5f\u80fd\u3068\u3001\u305d\u308c\u3089\u3092\u6d3b\u7528\u3057\u305fsubstr\u306e\u6700\u65b0\u306e\u4f7f\u7528\u30d1\u30bf\u30fc\u30f3\u3092\u7d39\u4ecb\u3057\u307e\u3059\u3002<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>std::span\u3068\u306e\u9023\u643a<\/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;string&gt;\n#include &lt;span&gt;\n#include &lt;iostream&gt;\n\nclass ModernStringProcessor {\npublic:\n    \/\/ std::span\u3092\u4f7f\u7528\u3057\u305f\u52b9\u7387\u7684\u306a\u6587\u5b57\u5217\u51e6\u7406\n    template&lt;typename T&gt;\n    static void processSubstrings(std::span&lt;T&gt; data) {\n        for (const auto&amp; str : data) {\n            if (auto substr = str.substr(0, 5); !substr.empty()) {\n                processChunk(substr);\n            }\n        }\n    }\n\nprivate:\n    static void processChunk(const std::string&amp; chunk) {\n        std::cout &lt;&lt; \"Processing: \" &lt;&lt; chunk &lt;&lt; std::endl;\n    }\n};\n\n\/\/ \u4f7f\u7528\u4f8b\nint main() {\n    std::vector&lt;std::string&gt; strings = {\n        \"Hello, World!\",\n        \"Modern C++\",\n        \"Programming\"\n    };\n\n    ModernStringProcessor::processSubstrings(strings);\n    return 0;\n}<\/pre>\n\n\n\n<ol start=\"2\" class=\"wp-block-list\">\n<li><strong>Ranges library\u3068\u306e\u7d71\u5408<\/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;string&gt;\n#include &lt;ranges&gt;\n#include &lt;iostream&gt;\n\nclass RangeBasedProcessor {\npublic:\n    static auto splitIntoViews(const std::string&amp; str, char delimiter) {\n        return str \n            | std::views::split(delimiter)\n            | std::views::transform([](auto&amp;&amp; rng) {\n                return std::string_view(\n                    &amp;*rng.begin(),\n                    std::ranges::distance(rng)\n                );\n            });\n    }\n\n    static void processWithRanges(const std::string&amp; input) {\n        auto words = splitIntoViews(input, ' ');\n\n        for (const auto&amp; word : words) {\n            \/\/ \u5404\u5358\u8a9e\u306e\u5148\u982d3\u6587\u5b57\u3092\u62bd\u51fa\n            if (word.length() &gt;= 3) {\n                auto prefix = std::string_view(word.data(), 3);\n                std::cout &lt;&lt; \"Prefix: \" &lt;&lt; prefix &lt;&lt; std::endl;\n            }\n        }\n    }\n};\n\n\/\/ \u4f7f\u7528\u4f8b\nvoid demonstrate_ranges() {\n    std::string text = \"Modern C++ Programming Language\";\n    RangeBasedProcessor::processWithRanges(text);\n}<\/pre>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-17\">\u65b0\u6a5f\u80fd\u3068\u306e\u7d44\u307f\u5408\u308f\u305b\u306b\u3088\u308b\u52b9\u679c\u7684\u306a\u5b9f\u88c5<\/h3>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>Concepts\u3092\u6d3b\u7528\u3057\u305f\u578b\u5b89\u5168\u306a\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=\"\">#include &lt;string&gt;\n#include &lt;concepts&gt;\n#include &lt;type_traits&gt;\n\n\/\/ \u6587\u5b57\u5217\u578b\u3092\u8868\u3059concept\ntemplate&lt;typename T&gt;\nconcept StringLike = requires(T t) {\n    { t.substr(0) } -&gt; std::convertible_to&lt;std::string&gt;;\n    { t.length() } -&gt; std::convertible_to&lt;size_t&gt;;\n    { t.data() } -&gt; std::convertible_to&lt;const char*&gt;;\n};\n\ntemplate&lt;StringLike T&gt;\nclass ModernStringHandler {\npublic:\n    static auto safeSubstring(const T&amp; str, size_t pos, size_t len = std::string::npos) {\n        if constexpr (std::is_same_v&lt;T, std::string&gt;) {\n            return str.substr(pos, len);\n        } else {\n            return std::string(str).substr(pos, len);\n        }\n    }\n\n    static auto getView(const T&amp; str, size_t pos, size_t len = std::string::npos) {\n        return std::string_view(str.data() + pos, \n            std::min(len, str.length() - pos));\n    }\n};\n\n\/\/ \u4f7f\u7528\u4f8b\nvoid demonstrate_concepts() {\n    std::string str = \"Hello, Modern C++!\";\n    auto handler = ModernStringHandler&lt;std::string&gt;();\n\n    auto substr = handler.safeSubstring(str, 7, 6);  \/\/ \"Modern\"\n    auto view = handler.getView(str, 7, 6);          \/\/ \"Modern\"\n}<\/pre>\n\n\n\n<ol start=\"2\" class=\"wp-block-list\">\n<li><strong>\u30b3\u30eb\u30fc\u30c1\u30f3\u3092\u4f7f\u7528\u3057\u305f\u52b9\u7387\u7684\u306a\u6587\u5b57\u5217\u51e6\u7406<\/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;string&gt;\n#include &lt;coroutine&gt;\n#include &lt;memory&gt;\n\nclass SubstringGenerator {\npublic:\n    struct promise_type;\n    using handle_type = std::coroutine_handle&lt;promise_type&gt;;\n\n    struct promise_type {\n        std::string current_value;\n\n        SubstringGenerator get_return_object() {\n            return SubstringGenerator(handle_type::from_promise(*this));\n        }\n\n        std::suspend_always initial_suspend() { return {}; }\n        std::suspend_always final_suspend() noexcept { return {}; }\n        void return_void() {}\n        void unhandled_exception() {}\n\n        std::suspend_always yield_value(std::string value) {\n            current_value = std::move(value);\n            return {};\n        }\n    };\n\n    SubstringGenerator(handle_type h) : handle(h) {}\n    ~SubstringGenerator() {\n        if (handle) handle.destroy();\n    }\n\n    std::string current_value() {\n        return handle.promise().current_value;\n    }\n\n    bool move_next() {\n        if (handle) {\n            handle.resume();\n            return !handle.done();\n        }\n        return false;\n    }\n\nprivate:\n    handle_type handle;\n};\n\n\/\/ \u30b3\u30eb\u30fc\u30c1\u30f3\u3092\u4f7f\u7528\u3057\u305f\u6587\u5b57\u5217\u51e6\u7406\nSubstringGenerator processStringAsync(const std::string&amp; input) {\n    const size_t chunk_size = 5;\n    size_t pos = 0;\n\n    while (pos &lt; input.length()) {\n        co_yield input.substr(pos, chunk_size);\n        pos += chunk_size;\n    }\n}\n\n\/\/ \u4f7f\u7528\u4f8b\nvoid demonstrate_coroutines() {\n    std::string text = \"Modern C++ Programming with Coroutines\";\n    auto generator = processStringAsync(text);\n\n    while (generator.move_next()) {\n        std::cout &lt;&lt; generator.current_value() &lt;&lt; std::endl;\n    }\n}<\/pre>\n\n\n\n<p>\u3053\u308c\u3089\u306e\u6700\u65b0\u6a5f\u80fd\u3092\u6d3b\u7528\u3059\u308b\u3053\u3068\u3067\u3001\u3088\u308a\u578b\u5b89\u5168\u3067\u52b9\u7387\u7684\u306a\u6587\u5b57\u5217\u51e6\u7406\u304c\u5b9f\u73fe\u3067\u304d\u307e\u3059\u3002C++20\u4ee5\u964d\u306e\u6a5f\u80fd\u3092\u9069\u5207\u306b\u7d44\u307f\u5408\u308f\u305b\u308b\u3053\u3068\u3067\u3001\u30b3\u30fc\u30c9\u306e\u54c1\u8cea\u3068\u4fdd\u5b88\u6027\u304c\u5411\u4e0a\u3057\u3001\u3088\u308a\u5805\u7262\u306a\u30a2\u30d7\u30ea\u30b1\u30fc\u30b7\u30e7\u30f3\u306e\u958b\u767a\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-1712","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\/1712","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=1712"}],"version-history":[{"count":1,"href":"https:\/\/dexall.co.jp\/articles\/index.php?rest_route=\/wp\/v2\/posts\/1712\/revisions"}],"predecessor-version":[{"id":1713,"href":"https:\/\/dexall.co.jp\/articles\/index.php?rest_route=\/wp\/v2\/posts\/1712\/revisions\/1713"}],"wp:attachment":[{"href":"https:\/\/dexall.co.jp\/articles\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1712"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/dexall.co.jp\/articles\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1712"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/dexall.co.jp\/articles\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1712"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}