318 lines
27 KiB
HTML
318 lines
27 KiB
HTML
<!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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<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
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<title>std::copy, std::copy_if</title>
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<link rel="stylesheet" href="ext.css" />
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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_copy 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>copy, <span style="font-size:0.7em; line-height:130%">std::</span>copy_if</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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<tbody>
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<tr class="t-dsc-header">
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<td>
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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>
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<td></td>
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<td></td>
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</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">(1)</td>
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<td></td>
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</tr>
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<tr class="t-dcl t-until-cxx20">
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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> InputIt, <span class="kw1">class</span> OutputIt <span class="sy1">></span><br />
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OutputIt copy<span class="br0">(</span> InputIt first, InputIt last, OutputIt d_first <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-until-cxx20">(C++20 前)</span></td>
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</tr>
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<tr class="t-dcl t-since-cxx20">
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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> InputIt, <span class="kw1">class</span> OutputIt <span class="sy1">></span><br />
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<span class="kw4">constexpr</span> OutputIt copy<span class="br0">(</span> InputIt first, InputIt last, OutputIt d_first <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-cxx20">(C++20 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 t-since-cxx17">
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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> ExecutionPolicy, <span class="kw1">class</span> ForwardIt1, <span class="kw1">class</span> ForwardIt2 <span class="sy1">></span><br />
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ForwardIt2 copy<span class="br0">(</span> ExecutionPolicy<span class="sy3">&&</span> policy, ForwardIt1 first, ForwardIt1 last, ForwardIt2 d_first <span class="br0">)</span><span class="sy4">;</span></span></div>
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</td>
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<td>(2)</td>
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<td><span class="t-mark-rev t-since-cxx17">(C++17 起)</span></td>
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</tr>
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</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-cxx20">
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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> InputIt, <span class="kw1">class</span> OutputIt, <span class="kw1">class</span> UnaryPredicate <span class="sy1">></span><br /></span>
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<p>OutputIt copy_if<span class="br0">(</span> InputIt first, InputIt last,<br />
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OutputIt d_first,<br /></p>
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UnaryPredicate pred <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-cxx20">(C++20 前)</span></td>
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</tr>
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<tr class="t-dcl t-since-cxx20">
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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> InputIt, <span class="kw1">class</span> OutputIt, <span class="kw1">class</span> UnaryPredicate <span class="sy1">></span><br /></span>
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<p><span class="kw4">constexpr</span> OutputIt copy_if<span class="br0">(</span> InputIt first, InputIt last,<br />
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OutputIt d_first,<br /></p>
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UnaryPredicate pred <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-cxx20">(C++20 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 t-since-cxx17">
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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> ExecutionPolicy, <span class="kw1">class</span> ForwardIt1, <span class="kw1">class</span> ForwardIt2, <span class="kw1">class</span> UnaryPredicate <span class="sy1">></span><br /></span>
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<p>ForwardIt2 copy_if<span class="br0">(</span> ExecutionPolicy<span class="sy3">&&</span> policy, ForwardIt1 first, ForwardIt1 last,<br />
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ForwardIt2 d_first,<br /></p>
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UnaryPredicate pred <span class="br0">)</span><span class="sy4">;</span></div>
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</td>
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<td>(4)</td>
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<td><span class="t-mark-rev t-since-cxx17">(C++17 起)</span></td>
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</tr>
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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>复制 <code>[first, last)</code> 所定义的范围中的元素到始于 <code>d_first</code> 的另一范围。</p>
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<div class="t-li1"><span class="t-li">1)</span> 复制范围 <code>[first, last)</code> 中的所有元素，从首元素开始逐次到末元素。若 <code>d_first</code> 在范围 <code>[first, last)</code> 中则行为未定义。此情况下可用 <span class="t-lc"><a href="cpp-algorithm-copy_backward.html">std::copy_backward</a></span> 代替。</div>
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<div class="t-li1"><span class="t-li">3)</span> 仅复制谓词 <code>pred</code> 对其返回 <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw2">true</span></span></span> 的元素。保持被复制元素的相对顺序。若源与目标范围重叠则行为未定义。</div>
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<div class="t-li1"><span class="t-li">2,4)</span> 同 <span class="t-v">(1,3)</span> ，但按照 <code>policy</code> 执行。这些重载仅若 <span class="t-rev-inl t-until-cxx20"><span><span class="t-c"><span class="mw-geshi cpp source-cpp"><a href="cpp-algorithm-is_execution_policy.html"><span class="kw1564">std::<span class="me2">is_execution_policy_v</span></span></a><span class="sy1"><</span><a href="cpp-types-decay.html"><span class="kw629">std::<span class="me2">decay_t</span></span></a><span class="sy1"><</span>ExecutionPolicy<span class="sy1">>></span></span></span></span> <span><span class="t-mark-rev t-until-cxx20">(C++20 前)</span></span></span><span class="t-rev-inl t-since-cxx20"><span><span class="t-c"><span class="mw-geshi cpp source-cpp"><a href="cpp-algorithm-is_execution_policy.html"><span class="kw1564">std::<span class="me2">is_execution_policy_v</span></span></a><span class="sy1"><</span>std<span class="sy4">::</span><span class="me2">remove_cvref_t</span><span class="sy1"><</span>ExecutionPolicy<span class="sy1">>></span></span></span></span> <span><span class="t-mark-rev t-since-cxx20">(C++20 起)</span></span></span> 为 true 才参与重载决议。</div>
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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>first, last</td>
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<td>-</td>
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<td>要复制的元素范围</td>
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</tr>
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<tr class="t-par">
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<td>d_first</td>
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<td>-</td>
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<td>目标范围的起始。</td>
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</tr>
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<tr class="t-par">
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<td>policy</td>
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<td>-</td>
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<td>所用的执行策略。细节见<a href="cpp-algorithm-execution_policy_tag_t.html">执行策略</a>。</td>
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</tr>
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<tr class="t-par">
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<td>pred</td>
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<td>-</td>
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<td>对所要求的元素则返回 ​<span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw2">true</span></span></span> 的一元谓词。<br />
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<p>对每个（可为 const 的） <code>VT</code> 类型参数 <code>v</code> ，其中 <code>VT</code> 是 <code>InputIt</code> 的值类型，表达式 <span class="t-c"><span class="mw-geshi cpp source-cpp">pred<span class="br0">(</span>v<span class="br0">)</span></span></span> 必须可转换为 <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw4">bool</span></span></span> ，无关乎<a href="cpp-language-value_category.html">值类别</a>，而且必须不修改 <code>v</code> 。从而不允许 <span class="t-c"><span class="mw-geshi cpp source-cpp">VT<span class="sy3">&</span></span></span> 类型参数<span class="t-rev-inl t-since-cxx11"><span>，亦不允许 <span class="t-c"><span class="mw-geshi cpp source-cpp">VT</span></span> ，除非对 <code>VT</code> 而言移动等价于复制</span> <span><span class="t-mark-rev t-since-cxx11">(C++11 起)</span></span></span>。 ​</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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<code>InputIt</code> 必须满足<a href="cpp-named_req-InputIterator.html"><span style="font-style:italic">老式输入迭代器</span> <span style="font-family: Georgia, 'DejaVu Serif', serif; font-style:italic">(LegacyInputIterator)</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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<code>OutputIt</code> 必须满足<a href="cpp-named_req-OutputIterator.html"><span style="font-style:italic">老式输出迭代器</span> <span style="font-family: Georgia, 'DejaVu Serif', serif; font-style:italic">(LegacyOutputIterator)</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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<code>ForwardIt1, ForwardIt2</code> 必须满足<a href="cpp-named_req-ForwardIterator.html"><span style="font-style:italic">老式向前迭代器</span> <span style="font-family: Georgia, 'DejaVu Serif', serif; font-style:italic">(LegacyForwardIterator)</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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<code>UnaryPredicate</code> 必须满足<a href="cpp-named_req-Predicate.html"><span style="font-style:italic">谓词</span> <span style="font-family: Georgia, 'DejaVu Serif', serif; font-style:italic">(Predicate)</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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<p>指向目标范围中最后复制元素的下个元素的输出迭代器。</p>
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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> 准确赋值 <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="br0">(</span>last <span class="sy2">-</span> first<span class="br0">)</span></span></span> 次</div>
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<div class="t-li1"><span class="t-li">3-4)</span> 准确应用 <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="br0">(</span>last <span class="sy2">-</span> first<span class="br0">)</span></span></span> 次谓词， <span class="t-c"><span class="mw-geshi cpp source-cpp">​<span class="nu0">0</span>​</span></span> 和 <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="br0">(</span>last <span class="sy2">-</span> first<span class="br0">)</span></span></span> 之间次赋值（对于每个谓词返回 <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw2">true</span></span></span> 的元素赋值，取决于谓词和输入数据）</div>
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<p>对于带 <code>ExecutionPolicy</code> 的重载，若 <code>ForwardIt1</code> 的值类型非<a href="cpp-named_req-MoveConstructible.html"><span style="font-style:italic">可移动构造</span> <span style="font-family: Georgia, 'DejaVu Serif', serif; font-style:italic">(MoveConstructible)</span></a> 则有性能开销。</p>
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<h3><span class="mw-headline" id=".E5.BC.82.E5.B8.B8">异常</span></h3>
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<p>拥有名为 <code>ExecutionPolicy</code> 的模板形参的重载按下列方式报告错误：</p>
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<ul>
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<li>若作为算法一部分调用的函数的执行抛出异常，且 <code>ExecutionPolicy</code> 为<a href="cpp-algorithm-execution_policy_tag_t.html">标准策略</a>之一，则调用 <span class="t-lc"><a href="cpp-error-terminate.html">std::terminate</a></span> 。对于任何其他 <code>ExecutionPolicy</code> ，行为是实现定义的。</li>
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<li>若算法无法分配内存，则抛出 <span class="t-lc"><a href="cpp-memory-new-bad_alloc.html">std::bad_alloc</a></span> 。</li>
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</ul>
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<h3><span class="mw-headline" id=".E6.B3.A8.E8.A7.A3">注解</span></h3>
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<p>实践中，若 <code>value_type</code> 为<a href="cpp-named_req-TriviallyCopyable.html"><span style="font-style:italic">可平凡复制</span> <span style="font-family: Georgia, 'DejaVu Serif', serif; font-style:italic">(TriviallyCopyable)</span></a> 而迭代器类型满足<a href="cpp-named_req-ContiguousIterator.html"><span style="font-style:italic">老式连续迭代器</span> <span style="font-family: Georgia, 'DejaVu Serif', serif; font-style:italic">(LegacyContiguousIterator)</span></a> ，则 <code>std::copy</code> 避免多次赋值并使用大批量复制函数，如 <span class="t-lc"><a href="cpp-string-byte-memmove.html">std::memmove</a></span> 。</p>
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<p>复制重叠的范围时， <code>std::copy</code> 在复制到左侧（目标范围起始在源范围之外）时适合，而 <code>std::copy_backward</code> 在复制到右侧（目标范围结尾在源范围之外）时适合。</p>
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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> InputIt, <span class="kw1">class</span> OutputIt<span class="sy1">></span>
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OutputIt copy<span class="br0">(</span>InputIt first, InputIt last,
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OutputIt d_first<span class="br0">)</span>
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<span class="br0">{</span>
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<span class="kw1">while</span> <span class="br0">(</span>first <span class="sy3">!</span><span class="sy1">=</span> last<span class="br0">)</span> <span class="br0">{</span>
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<span class="sy2">*</span>d_first<span class="sy2">++</span> <span class="sy1">=</span> <span class="sy2">*</span>first<span class="sy2">++</span><span class="sy4">;</span>
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<span class="br0">}</span>
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<span class="kw1">return</span> d_first<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">
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<pre class="de1"><span class="kw1">template</span><span class="sy1"><</span><span class="kw1">class</span> InputIt, <span class="kw1">class</span> OutputIt, <span class="kw1">class</span> UnaryPredicate<span class="sy1">></span>
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OutputIt copy_if<span class="br0">(</span>InputIt first, InputIt last,
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OutputIt d_first, UnaryPredicate pred<span class="br0">)</span>
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<span class="br0">{</span>
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<span class="kw1">while</span> <span class="br0">(</span>first <span class="sy3">!</span><span class="sy1">=</span> last<span class="br0">)</span> <span class="br0">{</span>
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<span class="kw1">if</span> <span class="br0">(</span>pred<span class="br0">(</span><span class="sy2">*</span>first<span class="br0">)</span><span class="br0">)</span>
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<span class="sy2">*</span>d_first<span class="sy2">++</span> <span class="sy1">=</span> <span class="sy2">*</span>first<span class="sy4">;</span>
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<span class="sy2">++</span>first<span class="sy4">;</span>
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<span class="br0">}</span>
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<span class="kw1">return</span> d_first<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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</table>
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<h3><span class="mw-headline" id=".E7.A4.BA.E4.BE.8B">示例</span></h3>
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<div class="t-example">
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<p>下列代码用 <code>copy</code> 复制一个 <code>vector</code> 的内容到另一个，并显示结果 <code>vector</code> ：</p>
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<div class="t-example-live-link"></div>
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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="co2">#include <algorithm></span>
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<span class="co2">#include <iostream></span>
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<span class="co2">#include <vector></span>
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<span class="co2">#include <iterator></span>
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<span class="co2">#include <numeric></span>
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<span class="kw4">int</span> main<span class="br0">(</span><span class="br0">)</span>
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<span class="br0">{</span>
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<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> from_vector<span class="br0">(</span><span class="nu0">10</span><span class="br0">)</span><span class="sy4">;</span>
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<a href="cpp-algorithm-iota.html"><span class="kw1653">std::<span class="me2">iota</span></span></a><span class="br0">(</span>from_vector.<span class="me1">begin</span><span class="br0">(</span><span class="br0">)</span>, from_vector.<span class="me1">end</span><span class="br0">(</span><span class="br0">)</span>, <span class="nu0">0</span><span class="br0">)</span><span class="sy4">;</span>
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<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> to_vector<span class="sy4">;</span>
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std<span class="sy4">::</span><span class="me2">copy</span><span class="br0">(</span>from_vector.<span class="me1">begin</span><span class="br0">(</span><span class="br0">)</span>, from_vector.<span class="me1">end</span><span class="br0">(</span><span class="br0">)</span>,
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<a href="cpp-iterator-back_inserter.html"><span class="kw665">std::<span class="me2">back_inserter</span></span></a><span class="br0">(</span>to_vector<span class="br0">)</span><span class="br0">)</span><span class="sy4">;</span>
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<span class="co1">// 或可选地，</span>
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<span class="co1">// std::vector<int> to_vector(from_vector.size());</span>
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<span class="co1">// std::copy(from_vector.begin(), from_vector.end(), to_vector.begin());</span>
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<span class="co1">// 任一方式都等价于</span>
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<span class="co1">// std::vector<int> to_vector = from_vector;</span>
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<a href="cpp-io-cout.html"><span class="kw1756">std::<span class="me2">cout</span></span></a> <span class="sy1"><<</span> <span class="st0">"to_vector contains: "</span><span class="sy4">;</span>
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std<span class="sy4">::</span><span class="me2">copy</span><span class="br0">(</span>to_vector.<span class="me1">begin</span><span class="br0">(</span><span class="br0">)</span>, to_vector.<span class="me1">end</span><span class="br0">(</span><span class="br0">)</span>,
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<a href="cpp-iterator-ostream_iterator.html"><span class="kw670">std::<span class="me2">ostream_iterator</span></span></a><span class="sy1"><</span><span class="kw4">int</span><span class="sy1">></span><span class="br0">(</span><a href="cpp-io-cout.html"><span class="kw1756">std::<span class="me2">cout</span></span></a>, <span class="st0">" "</span><span class="br0">)</span><span class="br0">)</span><span class="sy4">;</span>
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<a href="cpp-io-cout.html"><span class="kw1756">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>
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<a href="cpp-io-cout.html"><span class="kw1756">std::<span class="me2">cout</span></span></a> <span class="sy1"><<</span> <span class="st0">"odd numbers in to_vector are: "</span><span class="sy4">;</span>
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std<span class="sy4">::</span><span class="me2">copy_if</span><span class="br0">(</span>to_vector.<span class="me1">begin</span><span class="br0">(</span><span class="br0">)</span>, to_vector.<span class="me1">end</span><span class="br0">(</span><span class="br0">)</span>,
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<a href="cpp-iterator-ostream_iterator.html"><span class="kw670">std::<span class="me2">ostream_iterator</span></span></a><span class="sy1"><</span><span class="kw4">int</span><span class="sy1">></span><span class="br0">(</span><a href="cpp-io-cout.html"><span class="kw1756">std::<span class="me2">cout</span></span></a>, <span class="st0">" "</span><span class="br0">)</span>,
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<span class="br0">[</span><span class="br0">]</span><span class="br0">(</span><span class="kw4">int</span> x<span class="br0">)</span> <span class="br0">{</span> <span class="kw1">return</span> <span class="br0">(</span>x <span class="sy2">%</span> <span class="nu0">2</span><span class="br0">)</span> <span class="sy1">==</span> <span class="nu0">1</span><span class="sy4">;</span> <span class="br0">}</span><span class="br0">)</span><span class="sy4">;</span>
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<a href="cpp-io-cout.html"><span class="kw1756">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>
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<span class="br0">}</span></pre></div>
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</div>
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<p>输出：</p>
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<div dir="ltr" class="mw-geshi" style="text-align: left;">
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<div class="text source-text">
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<pre class="de1">to_vector contains: 0 1 2 3 4 5 6 7 8 9
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odd numbers in to_vector are: 1 3 5 7 9</pre></div>
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</div>
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</div>
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<h3><span class="mw-headline" id=".E5.8F.82.E9.98.85">参阅</span></h3>
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<table class="t-dsc-begin">
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<tr class="t-dsc">
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<td>
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<div class="t-dsc-member-div">
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<div><a href="cpp-algorithm-copy_backward.html"><span class="t-lines"><span>copy_backward</span></span></a></div>
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</div>
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</td>
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<td>按从后往前的顺序复制一个范围内的元素<br />
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<span class="t-mark">(函数模板)</span></td>
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</tr>
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<tr class="t-dsc">
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<td>
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<div class="t-dsc-member-div">
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<div><a href="cpp-algorithm-reverse_copy.html"><span class="t-lines"><span>reverse_copy</span></span></a></div>
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</div>
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</td>
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<td>创建一个范围的逆向副本<br />
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<span class="t-mark">(函数模板)</span></td>
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</tr>
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<tr class="t-dsc">
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<td>
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<div class="t-dsc-member-div">
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<div><a href="cpp-algorithm-copy_n.html"><span class="t-lines"><span>copy_n</span></span></a></div>
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<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx11">(C++11)</span></span></span></div>
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</div>
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</td>
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<td>将一定数目的元素复制到一个新的位置<br />
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<span class="t-mark">(函数模板)</span></td>
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</tr>
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<tr class="t-dsc">
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<td>
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<div class="t-dsc-member-div">
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<div><a href="cpp-algorithm-fill.html"><span class="t-lines"><span>fill</span></span></a></div>
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</div>
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</td>
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<td>将一个给定值复制赋值给一个范围内的每个元素<br />
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<span class="t-mark">(函数模板)</span></td>
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</tr>
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<tr class="t-dsc">
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<td>
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<div class="t-dsc-member-div">
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<div><a href="cpp-algorithm-remove_copy.html"><span class="t-lines"><span>remove_copy</span><span>remove_copy_if</span></span></a></div>
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</div>
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</td>
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<td>复制一个范围的元素，忽略满足特定判别标准的元素<br />
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<span class="t-mark">(函数模板)</span></td>
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</tr>
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</table>
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</div>
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<div class="visualClear"></div>
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</div>
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</div>
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</div>
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</body>
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</html>
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