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<!DOCTYPE html>
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<html lang="zh" dir="ltr" class="client-nojs" xmlns="http://www.w3.org/1999/xhtml" xml:lang="zh">
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<head><meta http-equiv="x-ua-compatible" content="ie=edge">
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<title>std::minmax</title>
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<link rel="stylesheet" href="site_modules.css" />
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<body class="mediawiki ltr sitedir-ltr ns-0 ns-subject page-cpp_algorithm_minmax skin-cppreference2 action-view cpp-navbar">
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<div id="cpp-content-base">
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<div id="content"><a id="top"></a>
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<h1 id="firstHeading" class="firstHeading"><span style="font-size:0.7em; line-height:130%">std::</span>minmax</h1>
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<div id="bodyContent">
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<div id="contentSub"><span class="subpages">< <a href="cpp.html">cpp</a>‎ | <a href="cpp-algorithm.html">algorithm</a></span></div>
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<div id="mw-content-text" lang="zh" dir="ltr" class="mw-content-ltr" xml:lang="zh">
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<table class="t-dcl-begin">
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<tr class="t-dsc-header">
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<div>定义于头文件 <code><a href="cpp-header-algorithm.html"><algorithm></a></code></div>
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<td></td>
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<td></td>
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<tbody class="t-dcl-rev t-dcl-rev-num">
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<td rowspan="142">(1)</td>
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<td></td>
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<tr class="t-dcl t-since-cxx11 t-until-cxx14">
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<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span> <span class="kw1">class</span> T <span class="sy1">></span><br />
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<a href="cpp-utility-pair.html"><span class="kw1096">std::<span class="me2">pair</span></span></a><span class="sy1"><</span><span class="kw4">const</span> T<span class="sy3">&</span>,<span class="kw4">const</span> T<span class="sy3">&</span><span class="sy1">></span> minmax<span class="br0">(</span> <span class="kw4">const</span> T<span class="sy3">&</span> a, <span class="kw4">const</span> T<span class="sy3">&</span> b <span class="br0">)</span><span class="sy4">;</span></span></div>
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</td>
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<td class="t-dcl-nopad"></td>
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<td><span class="t-mark-rev t-since-cxx11">(C++11 起)</span><br />
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<span class="t-mark-rev t-until-cxx14">(C++14 前)</span></td>
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</tr>
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<tr class="t-dcl t-since-cxx14">
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<td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span> <span class="kw1">class</span> T <span class="sy1">></span><br />
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<span class="kw4">constexpr</span> <a href="cpp-utility-pair.html"><span class="kw1096">std::<span class="me2">pair</span></span></a><span class="sy1"><</span><span class="kw4">const</span> T<span class="sy3">&</span>,<span class="kw4">const</span> T<span class="sy3">&</span><span class="sy1">></span> minmax<span class="br0">(</span> <span class="kw4">const</span> T<span class="sy3">&</span> a, <span class="kw4">const</span> T<span class="sy3">&</span> b <span class="br0">)</span><span class="sy4">;</span></span></div>
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</td>
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<td class="t-dcl-nopad"></td>
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<td><span class="t-mark-rev t-since-cxx14">(C++14 起)</span></td>
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</tr>
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</tbody>
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<tbody></tbody>
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<tbody class="t-dcl-rev t-dcl-rev-num">
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<tr class="t-dcl-rev-aux">
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<td></td>
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<td rowspan="142">(2)</td>
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<td></td>
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</tr>
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<tr class="t-dcl t-since-cxx11 t-until-cxx14">
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<td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span> <span class="kw1">class</span> T, <span class="kw1">class</span> Compare <span class="sy1">></span><br /></span>
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<p><a href="cpp-utility-pair.html"><span class="kw1096">std::<span class="me2">pair</span></span></a><span class="sy1"><</span><span class="kw4">const</span> T<span class="sy3">&</span>,<span class="kw4">const</span> T<span class="sy3">&</span><span class="sy1">></span> minmax<span class="br0">(</span> <span class="kw4">const</span> T<span class="sy3">&</span> a, <span class="kw4">const</span> T<span class="sy3">&</span> b,<br /></p>
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Compare comp <span class="br0">)</span><span class="sy4">;</span></div>
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</td>
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<td class="t-dcl-nopad"></td>
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<td><span class="t-mark-rev t-since-cxx11">(C++11 起)</span><br />
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<span class="t-mark-rev t-until-cxx14">(C++14 前)</span></td>
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</tr>
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<tr class="t-dcl t-since-cxx14">
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<td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span> <span class="kw1">class</span> T, <span class="kw1">class</span> Compare <span class="sy1">></span><br /></span>
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<p><span class="kw4">constexpr</span> <a href="cpp-utility-pair.html"><span class="kw1096">std::<span class="me2">pair</span></span></a><span class="sy1"><</span><span class="kw4">const</span> T<span class="sy3">&</span>,<span class="kw4">const</span> T<span class="sy3">&</span><span class="sy1">></span> minmax<span class="br0">(</span> <span class="kw4">const</span> T<span class="sy3">&</span> a, <span class="kw4">const</span> T<span class="sy3">&</span> b,<br /></p>
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Compare comp <span class="br0">)</span><span class="sy4">;</span></div>
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</td>
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<td class="t-dcl-nopad"></td>
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<td><span class="t-mark-rev t-since-cxx14">(C++14 起)</span></td>
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</tr>
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</tbody>
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<tbody></tbody>
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<tbody class="t-dcl-rev t-dcl-rev-num">
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<tr class="t-dcl-rev-aux">
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<td></td>
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<td rowspan="142">(3)</td>
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<td></td>
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</tr>
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<tr class="t-dcl t-since-cxx11 t-until-cxx14">
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<td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span> <span class="kw1">class</span> T <span class="sy1">></span><br />
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<a href="cpp-utility-pair.html"><span class="kw1096">std::<span class="me2">pair</span></span></a><span class="sy1"><</span>T,T<span class="sy1">></span> minmax<span class="br0">(</span> <a href="cpp-utility-initializer_list.html"><span class="kw960">std::<span class="me2">initializer_list</span></span></a><span class="sy1"><</span>T<span class="sy1">></span> ilist<span class="br0">)</span><span class="sy4">;</span></span></div>
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</td>
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<td class="t-dcl-nopad"></td>
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<td><span class="t-mark-rev t-since-cxx11">(C++11 起)</span><br />
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<span class="t-mark-rev t-until-cxx14">(C++14 前)</span></td>
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</tr>
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<tr class="t-dcl t-since-cxx14">
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<td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span> <span class="kw1">class</span> T <span class="sy1">></span><br />
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<span class="kw4">constexpr</span> <a href="cpp-utility-pair.html"><span class="kw1096">std::<span class="me2">pair</span></span></a><span class="sy1"><</span>T,T<span class="sy1">></span> minmax<span class="br0">(</span> <a href="cpp-utility-initializer_list.html"><span class="kw960">std::<span class="me2">initializer_list</span></span></a><span class="sy1"><</span>T<span class="sy1">></span> ilist<span class="br0">)</span><span class="sy4">;</span></span></div>
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</td>
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<td class="t-dcl-nopad"></td>
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<td><span class="t-mark-rev t-since-cxx14">(C++14 起)</span></td>
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</tr>
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</tbody>
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<tbody></tbody>
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<tbody class="t-dcl-rev t-dcl-rev-num">
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<tr class="t-dcl-rev-aux">
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<td></td>
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<td rowspan="142">(4)</td>
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<td></td>
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</tr>
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<tr class="t-dcl t-since-cxx11 t-until-cxx14">
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<td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span> <span class="kw1">class</span> T, <span class="kw1">class</span> Compare <span class="sy1">></span><br />
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<a href="cpp-utility-pair.html"><span class="kw1096">std::<span class="me2">pair</span></span></a><span class="sy1"><</span>T,T<span class="sy1">></span> minmax<span class="br0">(</span> <a href="cpp-utility-initializer_list.html"><span class="kw960">std::<span class="me2">initializer_list</span></span></a><span class="sy1"><</span>T<span class="sy1">></span> ilist, Compare comp <span class="br0">)</span><span class="sy4">;</span></span></div>
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</td>
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<td class="t-dcl-nopad"></td>
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<td><span class="t-mark-rev t-since-cxx11">(C++11 起)</span><br />
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<span class="t-mark-rev t-until-cxx14">(C++14 前)</span></td>
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</tr>
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<tr class="t-dcl t-since-cxx14">
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<td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span> <span class="kw1">class</span> T, <span class="kw1">class</span> Compare <span class="sy1">></span><br />
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<span class="kw4">constexpr</span> <a href="cpp-utility-pair.html"><span class="kw1096">std::<span class="me2">pair</span></span></a><span class="sy1"><</span>T,T<span class="sy1">></span> minmax<span class="br0">(</span> <a href="cpp-utility-initializer_list.html"><span class="kw960">std::<span class="me2">initializer_list</span></span></a><span class="sy1"><</span>T<span class="sy1">></span> ilist, Compare comp <span class="br0">)</span><span class="sy4">;</span></span></div>
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</td>
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<td class="t-dcl-nopad"></td>
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<td><span class="t-mark-rev t-since-cxx14">(C++14 起)</span></td>
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</tr>
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</tbody>
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<tbody>
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<tr class="t-dcl-sep">
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<td></td>
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<td></td>
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<td></td>
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</tr>
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</tbody>
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</table>
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<p>返回给定值的最小和最大者。</p>
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<div class="t-li1"><span class="t-li">1-2)</span> 返回到 <code>a</code> 的 <code>b</code> 较小和较大者的引用。</div>
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<div class="t-li1"><span class="t-li">3-4)</span> 返回 initializer_list <code>ilist</code> 中值的最小和最大者。</div>
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<p><span class="t-v">(1,3)</span> 版本用 <span class="t-c"><span class="mw-geshi cpp source-cpp">operator<span class="sy1"><</span></span></span> 比较值，而 <span class="t-v">(2,4)</span> 版本用给定的比较函数 <code>comp</code> 。</p>
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<h3><span class="mw-headline" id=".E5.8F.82.E6.95.B0">参数</span></h3>
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<table class="t-par-begin">
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<tr class="t-par">
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<td>a, b</td>
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<td>-</td>
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<td>要比较的值</td>
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</tr>
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<tr class="t-par">
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<td>ilist</td>
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<td>-</td>
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<td>含要比较的值的 initializer_list</td>
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</tr>
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<tr class="t-par">
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<td>comp</td>
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<td>-</td>
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<td>比较函数对象（即满足<a href="cpp-named_req-Compare.html"><span style="font-style:italic">比较</span> <span style="font-family: Georgia, 'DejaVu Serif', serif; font-style:italic">(Compare)</span></a> 要求的对象），若首个参数<i>小于</i>第二个，则返回 ​<span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw2">true</span></span></span> 。<br />
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<p>比较函数的签名应等价于如下：</p>
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<p><span class="t-cc"><span class="mw-geshi cpp source-cpp"> <span class="kw4">bool</span> cmp<span class="br0">(</span><span class="kw4">const</span> Type1 <span class="sy3">&</span>a, <span class="kw4">const</span> Type2 <span class="sy3">&</span>b<span class="br0">)</span><span class="sy4">;</span></span></span></p>
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<p>虽然签名不必有 <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw4">const</span> <span class="sy3">&</span></span></span> ，函数也不能修改传递给它的对象，而且必须接受（可为 const 的）类型 <code>Type1</code> 与 <code>Type2</code> 的值，无关乎<a href="cpp-language-value_category.html">值类别</a>（从而不允许 <span class="t-c"><span class="mw-geshi cpp source-cpp">Type1 <span class="sy3">&</span></span></span> <span class="t-rev-inl t-since-cxx11"><span>，亦不允许 <span class="t-c"><span class="mw-geshi cpp source-cpp">Type1</span></span> ，除非 <code>Type1</code> 的移动等价于复制</span> <span><span class="t-mark-rev t-since-cxx11">(C++11 起)</span></span></span>）。<br />
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类型 <span class="t-c"><span class="mw-geshi cpp source-cpp">Type1</span></span> 与 <span class="t-c"><span class="mw-geshi cpp source-cpp">Type2</span></span> 必须使得 <span class="t-c"><span class="mw-geshi cpp source-cpp">T</span></span> 类型的对象能隐式转换到这两个类型。 ​</p>
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</td>
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</tr>
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<tr class="t-par-hitem">
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<td colspan="3">类型要求</td>
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</tr>
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<tr class="t-par-req">
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<td colspan="3">-
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<div class="spacer"></div>
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为使用重载 (1,3) ， <code>T</code> 必须满足<a href="cpp-named_req-LessThanComparable.html"><span style="font-style:italic">可小于比较</span> <span style="font-family: Georgia, 'DejaVu Serif', serif; font-style:italic">(LessThanComparable)</span></a> 的要求。</td>
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</tr>
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<tr class="t-par-req">
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<td colspan="3">-
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<div class="spacer"></div>
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为使用重载 (3,4) ， <code>T</code> 必须满足<a href="cpp-named_req-CopyConstructible.html"><span style="font-style:italic">可复制构造</span> <span style="font-family: Georgia, 'DejaVu Serif', serif; font-style:italic">(CopyConstructible)</span></a> 的要求。</td>
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</tr>
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</table>
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<h3><span class="mw-headline" id=".E8.BF.94.E5.9B.9E.E5.80.BC">返回值</span></h3>
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<div class="t-li1"><span class="t-li">1-2)</span> 若 <code>a<b</code> 或若 <code>a</code> 等价于 <code>b</code> 则返回 <span class="t-c"><span class="mw-geshi cpp source-cpp"><a href="cpp-utility-pair.html"><span class="kw1096">std::<span class="me2">pair</span></span></a><span class="sy1"><</span><span class="kw4">const</span> T<span class="sy3">&</span>, <span class="kw4">const</span> T<span class="sy3">&</span><span class="sy1">></span><span class="br0">(</span>a, b<span class="br0">)</span></span></span> 的结果。若 <code>b<a</code> 则返回 <span class="t-c"><span class="mw-geshi cpp source-cpp"><a href="cpp-utility-pair.html"><span class="kw1096">std::<span class="me2">pair</span></span></a><span class="sy1"><</span><span class="kw4">const</span> T<span class="sy3">&</span>, <span class="kw4">const</span> T<span class="sy3">&</span><span class="sy1">></span><span class="br0">(</span>b, a<span class="br0">)</span></span></span> 的结果。</div>
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<div class="t-li1"><span class="t-li">3-4)</span> 以 <code>ilist</code> 中最小元素为第一元素，最大元素为第二元素的 pair 。若有数个元素等价于最小者，则返回最左的这种元素。若有数个元素等价于最大者，则返回最右的这种元素。</div>
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<h3><span class="mw-headline" id=".E5.A4.8D.E6.9D.82.E5.BA.A6">复杂度</span></h3>
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<div class="t-li1"><span class="t-li">1-2)</span> 准确一次比较</div>
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<div class="t-li1"><span class="t-li">3-4)</span> 至多 <code>ilist.size() * 3 / 2</code> 次比较</div>
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<h3><span class="mw-headline" id=".E5.8F.AF.E8.83.BD.E7.9A.84.E5.AE.9E.E7.8E.B0">可能的实现</span></h3>
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<table class="eq-fun-cpp-table">
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<tr>
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<th>版本一</th>
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</tr>
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<tr>
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<td>
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<div dir="ltr" class="mw-geshi" style="text-align: left;">
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<div class="cpp source-cpp">
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<pre class="de1"><span class="kw1">template</span><span class="sy1"><</span><span class="kw1">class</span> T<span class="sy1">></span>
|
||||
<span class="kw4">constexpr</span> <a href="cpp-utility-pair.html"><span class="kw1096">std::<span class="me2">pair</span></span></a><span class="sy1"><</span><span class="kw4">const</span> T<span class="sy3">&</span>, <span class="kw4">const</span> T<span class="sy3">&</span><span class="sy1">></span> minmax<span class="br0">(</span> <span class="kw4">const</span> T<span class="sy3">&</span> a, <span class="kw4">const</span> T<span class="sy3">&</span> b <span class="br0">)</span>
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||||
<span class="br0">{</span>
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||||
<span class="kw1">return</span> <span class="br0">(</span>b <span class="sy1"><</span> a<span class="br0">)</span> <span class="sy4">?</span> <a href="cpp-utility-pair.html"><span class="kw1096">std::<span class="me2">pair</span></span></a><span class="sy1"><</span><span class="kw4">const</span> T<span class="sy3">&</span>, <span class="kw4">const</span> T<span class="sy3">&</span><span class="sy1">></span><span class="br0">(</span>b, a<span class="br0">)</span>
|
||||
<span class="sy4">:</span> <a href="cpp-utility-pair.html"><span class="kw1096">std::<span class="me2">pair</span></span></a><span class="sy1"><</span><span class="kw4">const</span> T<span class="sy3">&</span>, <span class="kw4">const</span> T<span class="sy3">&</span><span class="sy1">></span><span class="br0">(</span>a, b<span class="br0">)</span><span class="sy4">;</span>
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||||
<span class="br0">}</span></pre></div>
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</div>
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</td>
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</tr>
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<tr>
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<th>版本二</th>
|
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</tr>
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<tr>
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<td>
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<div dir="ltr" class="mw-geshi" style="text-align: left;">
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<div class="cpp source-cpp">
|
||||
<pre class="de1"><span class="kw1">template</span><span class="sy1"><</span><span class="kw1">class</span> T, <span class="kw1">class</span> Compare<span class="sy1">></span>
|
||||
<span class="kw4">constexpr</span> <a href="cpp-utility-pair.html"><span class="kw1096">std::<span class="me2">pair</span></span></a><span class="sy1"><</span><span class="kw4">const</span> T<span class="sy3">&</span>, <span class="kw4">const</span> T<span class="sy3">&</span><span class="sy1">></span> minmax<span class="br0">(</span> <span class="kw4">const</span> T<span class="sy3">&</span> a, <span class="kw4">const</span> T<span class="sy3">&</span> b, Compare comp <span class="br0">)</span>
|
||||
<span class="br0">{</span>
|
||||
<span class="kw1">return</span> comp<span class="br0">(</span>b, a<span class="br0">)</span> <span class="sy4">?</span> <a href="cpp-utility-pair.html"><span class="kw1096">std::<span class="me2">pair</span></span></a><span class="sy1"><</span><span class="kw4">const</span> T<span class="sy3">&</span>, <span class="kw4">const</span> T<span class="sy3">&</span><span class="sy1">></span><span class="br0">(</span>b, a<span class="br0">)</span>
|
||||
<span class="sy4">:</span> <a href="cpp-utility-pair.html"><span class="kw1096">std::<span class="me2">pair</span></span></a><span class="sy1"><</span><span class="kw4">const</span> T<span class="sy3">&</span>, <span class="kw4">const</span> T<span class="sy3">&</span><span class="sy1">></span><span class="br0">(</span>a, b<span class="br0">)</span><span class="sy4">;</span>
|
||||
<span class="br0">}</span></pre></div>
|
||||
</div>
|
||||
</td>
|
||||
</tr>
|
||||
<tr>
|
||||
<th>版本三</th>
|
||||
</tr>
|
||||
<tr>
|
||||
<td>
|
||||
<div dir="ltr" class="mw-geshi" style="text-align: left;">
|
||||
<div class="cpp source-cpp">
|
||||
<pre class="de1"><span class="kw1">template</span><span class="sy1"><</span> <span class="kw1">class</span> T <span class="sy1">></span>
|
||||
<span class="kw4">constexpr</span> <a href="cpp-utility-pair.html"><span class="kw1096">std::<span class="me2">pair</span></span></a><span class="sy1"><</span>T, T<span class="sy1">></span> minmax<span class="br0">(</span> <a href="cpp-utility-initializer_list.html"><span class="kw960">std::<span class="me2">initializer_list</span></span></a><span class="sy1"><</span>T<span class="sy1">></span> ilist <span class="br0">)</span>
|
||||
<span class="br0">{</span>
|
||||
<span class="kw4">auto</span> p <span class="sy1">=</span> <a href="cpp-algorithm-minmax_element.html"><span class="kw1644">std::<span class="me2">minmax_element</span></span></a><span class="br0">(</span>ilist.<span class="me1">begin</span><span class="br0">(</span><span class="br0">)</span>, ilist.<span class="me1">end</span><span class="br0">(</span><span class="br0">)</span><span class="br0">)</span><span class="sy4">;</span>
|
||||
<span class="kw1">return</span> <a href="cpp-utility-pair.html"><span class="kw1096">std::<span class="me2">pair</span></span></a><span class="br0">(</span><span class="sy2">*</span>p.<span class="me1">first</span>, <span class="sy2">*</span>p.<span class="me1">second</span><span class="br0">)</span><span class="sy4">;</span>
|
||||
<span class="br0">}</span></pre></div>
|
||||
</div>
|
||||
</td>
|
||||
</tr>
|
||||
<tr>
|
||||
<th>版本四</th>
|
||||
</tr>
|
||||
<tr>
|
||||
<td>
|
||||
<div dir="ltr" class="mw-geshi" style="text-align: left;">
|
||||
<div class="cpp source-cpp">
|
||||
<pre class="de1"><span class="kw1">template</span><span class="sy1"><</span> <span class="kw1">class</span> T, <span class="kw1">class</span> Compare <span class="sy1">></span>
|
||||
<span class="kw4">constexpr</span> <a href="cpp-utility-pair.html"><span class="kw1096">std::<span class="me2">pair</span></span></a><span class="sy1"><</span>T, T<span class="sy1">></span> minmax<span class="br0">(</span> <a href="cpp-utility-initializer_list.html"><span class="kw960">std::<span class="me2">initializer_list</span></span></a><span class="sy1"><</span>T<span class="sy1">></span> ilist, Compare comp <span class="br0">)</span>
|
||||
<span class="br0">{</span>
|
||||
<span class="kw4">auto</span> p <span class="sy1">=</span> <a href="cpp-algorithm-minmax_element.html"><span class="kw1644">std::<span class="me2">minmax_element</span></span></a><span class="br0">(</span>ilist.<span class="me1">begin</span><span class="br0">(</span><span class="br0">)</span>, ilist.<span class="me1">end</span><span class="br0">(</span><span class="br0">)</span>, comp<span class="br0">)</span><span class="sy4">;</span>
|
||||
<span class="kw1">return</span> <a href="cpp-utility-pair.html"><span class="kw1096">std::<span class="me2">pair</span></span></a><span class="br0">(</span><span class="sy2">*</span>p.<span class="me1">first</span>, <span class="sy2">*</span>p.<span class="me1">second</span><span class="br0">)</span><span class="sy4">;</span>
|
||||
<span class="br0">}</span></pre></div>
|
||||
</div>
|
||||
</td>
|
||||
</tr>
|
||||
</table>
|
||||
<h3><span class="mw-headline" id=".E6.B3.A8.E8.A7.A3">注解</span></h3>
|
||||
<p>对于重载 <span class="t-v">(1,2)</span> ，若参数之一为临时量，则返回的引用在包含对 <code>minmax</code> 调用的完整表达式结尾变为悬垂引用：</p>
|
||||
<div dir="ltr" class="mw-geshi" style="text-align: left;">
|
||||
<div class="cpp source-cpp">
|
||||
<pre class="de1"><span class="kw4">int</span> n <span class="sy1">=</span> <span class="nu0">1</span><span class="sy4">;</span>
|
||||
<span class="kw4">auto</span> p <span class="sy1">=</span> std<span class="sy4">::</span><span class="me2">minmax</span><span class="br0">(</span>n, n<span class="sy2">+</span><span class="nu0">1</span><span class="br0">)</span><span class="sy4">;</span>
|
||||
<span class="kw4">int</span> m <span class="sy1">=</span> p.<span class="me1">first</span><span class="sy4">;</span> <span class="co1">// ok</span>
|
||||
<span class="kw4">int</span> x <span class="sy1">=</span> p.<span class="me1">second</span><span class="sy4">;</span> <span class="co1">// 未定义行为</span>
|
||||
|
||||
<span class="co1">// 注意结构化绑定有同样的问题</span>
|
||||
<span class="kw4">auto</span> <span class="br0">[</span>mm, xx<span class="br0">]</span> <span class="sy1">=</span> std<span class="sy4">::</span><span class="me2">minmax</span><span class="br0">(</span>n, n<span class="sy2">+</span><span class="nu0">1</span><span class="br0">)</span><span class="sy4">;</span>
|
||||
xx<span class="sy4">;</span> <span class="co1">// 未定义行为</span></pre></div>
|
||||
</div>
|
||||
<h3><span class="mw-headline" id=".E7.A4.BA.E4.BE.8B">示例</span></h3>
|
||||
<div class="t-example">
|
||||
<div class="t-example-live-link"></div>
|
||||
<div dir="ltr" class="mw-geshi" style="text-align: left;">
|
||||
<div class="cpp source-cpp">
|
||||
<pre class="de1"><span class="co2">#include <algorithm></span>
|
||||
<span class="co2">#include <iostream></span>
|
||||
<span class="co2">#include <vector></span>
|
||||
<span class="co2">#include <cstdlib></span>
|
||||
<span class="co2">#include <ctime></span>
|
||||
|
||||
<span class="kw4">int</span> main<span class="br0">(</span><span class="br0">)</span>
|
||||
<span class="br0">{</span>
|
||||
<a href="cpp-container-vector.html"><span class="kw1269">std::<span class="me2">vector</span></span></a><span class="sy1"><</span><span class="kw4">int</span><span class="sy1">></span> v <span class="br0">{</span><span class="nu0">3</span>, <span class="nu0">1</span>, <span class="nu0">4</span>, <span class="nu0">1</span>, <span class="nu0">5</span>, <span class="nu0">9</span>, <span class="nu0">2</span>, <span class="nu0">6</span><span class="br0">}</span><span class="sy4">;</span>
|
||||
<a href="cpp-numeric-random-srand.html"><span class="kw1497">std::<span class="me2">srand</span></span></a><span class="br0">(</span><a href="cpp-chrono-c-time.html"><span class="kw1011">std::<span class="me2">time</span></span></a><span class="br0">(</span><span class="nu0">0</span><span class="br0">)</span><span class="br0">)</span><span class="sy4">;</span>
|
||||
<a href="cpp-utility-pair.html"><span class="kw1096">std::<span class="me2">pair</span></span></a><span class="sy1"><</span><span class="kw4">int</span>, <span class="kw4">int</span><span class="sy1">></span> bounds <span class="sy1">=</span> std<span class="sy4">::</span><span class="me2">minmax</span><span class="br0">(</span><a href="cpp-numeric-random-rand.html"><span class="kw1498">std::<span class="me2">rand</span></span></a><span class="br0">(</span><span class="br0">)</span> <span class="sy2">%</span> v.<span class="me1">size</span><span class="br0">(</span><span class="br0">)</span>,
|
||||
<a href="cpp-numeric-random-rand.html"><span class="kw1498">std::<span class="me2">rand</span></span></a><span class="br0">(</span><span class="br0">)</span> <span class="sy2">%</span> v.<span class="me1">size</span><span class="br0">(</span><span class="br0">)</span><span class="br0">)</span><span class="sy4">;</span>
|
||||
|
||||
<a href="cpp-io-cout.html"><span class="kw1757">std::<span class="me2">cout</span></span></a> <span class="sy1"><<</span> <span class="st0">"v["</span> <span class="sy1"><<</span> bounds.<span class="me1">first</span> <span class="sy1"><<</span> <span class="st0">","</span> <span class="sy1"><<</span> bounds.<span class="me1">second</span> <span class="sy1"><<</span> <span class="st0">"]: "</span><span class="sy4">;</span>
|
||||
<span class="kw1">for</span> <span class="br0">(</span><span class="kw4">int</span> i <span class="sy1">=</span> bounds.<span class="me1">first</span><span class="sy4">;</span> i <span class="sy1"><</span> bounds.<span class="me1">second</span><span class="sy4">;</span> <span class="sy2">++</span>i<span class="br0">)</span> <span class="br0">{</span>
|
||||
<a href="cpp-io-cout.html"><span class="kw1757">std::<span class="me2">cout</span></span></a> <span class="sy1"><<</span> v<span class="br0">[</span>i<span class="br0">]</span> <span class="sy1"><<</span> <span class="st0">' '</span><span class="sy4">;</span>
|
||||
<span class="br0">}</span>
|
||||
<a href="cpp-io-cout.html"><span class="kw1757">std::<span class="me2">cout</span></span></a> <span class="sy1"><<</span> <span class="st0">'<span class="es1">\n</span>'</span><span class="sy4">;</span>
|
||||
<span class="br0">}</span></pre></div>
|
||||
</div>
|
||||
<p>可能的输出：</p>
|
||||
<div dir="ltr" class="mw-geshi" style="text-align: left;">
|
||||
<div class="text source-text">
|
||||
<pre class="de1">v[2,7]: 4 1 5 9 2</pre></div>
|
||||
</div>
|
||||
</div>
|
||||
<h3><span class="mw-headline" id=".E5.8F.82.E9.98.85">参阅</span></h3>
|
||||
<table class="t-dsc-begin">
|
||||
<tr class="t-dsc">
|
||||
<td>
|
||||
<div class="t-dsc-member-div">
|
||||
<div><a href="cpp-algorithm-min.html"><span class="t-lines"><span>min</span></span></a></div>
|
||||
</div>
|
||||
</td>
|
||||
<td>返回各给定值中的较小者<br />
|
||||
<span class="t-mark">(函数模板)</span></td>
|
||||
</tr>
|
||||
<tr class="t-dsc">
|
||||
<td>
|
||||
<div class="t-dsc-member-div">
|
||||
<div><a href="cpp-algorithm-max.html"><span class="t-lines"><span>max</span></span></a></div>
|
||||
</div>
|
||||
</td>
|
||||
<td>返回各给定值中的较大者<br />
|
||||
<span class="t-mark">(函数模板)</span></td>
|
||||
</tr>
|
||||
<tr class="t-dsc">
|
||||
<td>
|
||||
<div class="t-dsc-member-div">
|
||||
<div><a href="cpp-algorithm-minmax_element.html"><span class="t-lines"><span>minmax_element</span></span></a></div>
|
||||
<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx11">(C++11)</span></span></span></div>
|
||||
</div>
|
||||
</td>
|
||||
<td>返回范围内的最小元素和最大元素<br />
|
||||
<span class="t-mark">(函数模板)</span></td>
|
||||
</tr>
|
||||
<tr class="t-dsc">
|
||||
<td>
|
||||
<div class="t-dsc-member-div">
|
||||
<div><a href="cpp-algorithm-ranges-minmax.html"><span class="t-lines"><span>ranges::minmax</span></span></a></div>
|
||||
<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx20">(C++20)</span></span></span></div>
|
||||
</div>
|
||||
</td>
|
||||
<td>返回两个元素的较小和较大者<br />
|
||||
<span class="t-mark">(niebloid)</span></td>
|
||||
</tr>
|
||||
</table>
|
||||
</div>
|
||||
<div class="visualClear"></div>
|
||||
</div>
|
||||
</div>
|
||||
</div>
|
||||
</body>
|
||||
</html>
|
||||
Reference in New Issue
Block a user