281 lines
29 KiB
HTML
281 lines
29 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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<title>std::ranges::equal_range</title>
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<body class="mediawiki ltr sitedir-ltr ns-0 ns-subject page-cpp_algorithm_ranges_equal_range skin-cppreference2 action-view cpp-navbar">
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<h1 id="firstHeading" class="firstHeading"><span style="font-size:0.7em; line-height:130%">std::ranges::</span>equal_range</h1>
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<div id="contentSub"><span class="subpages">< <a href="cpp.html">cpp</a>‎ | <a href="cpp-algorithm.html">algorithm</a>‎ | <a href="cpp-algorithm-ranges.html">ranges</a></span></div>
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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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<div>调用签名</div>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span> std<span class="sy4">::</span><span class="me2">forward_iterator</span> I, std<span class="sy4">::</span><span class="me2">sentinel_for</span><span class="sy1"><</span>I<span class="sy1">></span> S,<br /></span>
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<p> <span class="kw1">class</span> T, <span class="kw1">class</span> Proj <span class="sy1">=</span> std<span class="sy4">::</span><span class="me2">identity</span>,<br />
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std<span class="sy4">::</span><span class="me2">indirect_strict_weak_order</span><span class="sy1"><</span><br />
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<span class="kw4">const</span> T<span class="sy2">*</span>,<br />
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std<span class="sy4">::</span><span class="me2">projected</span><span class="sy1"><</span>I, Proj<span class="sy1">>></span> Comp <span class="sy1">=</span> ranges<span class="sy4">::</span><span class="me2">less</span> <span class="sy1">></span><br />
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<span class="kw4">constexpr</span> ranges<span class="sy4">::</span><span class="me2">subrange</span><span class="sy1"><</span>I<span class="sy1">></span><br /></p>
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equal_range<span class="br0">(</span>I first, S last, <span class="kw4">const</span> T<span class="sy3">&</span> value, Comp comp <span class="sy1">=</span> <span class="br0">{</span><span class="br0">}</span>, Proj proj <span class="sy1">=</span> <span class="br0">{</span><span class="br0">}</span><span class="br0">)</span><span class="sy4">;</span></div>
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</td>
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<td>(1)</td>
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<td><span class="t-mark-rev t-since-cxx20">(C++20 起)</span></td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span> std<span class="sy4">::</span><span class="me2">forward_range</span> R, <span class="kw1">class</span> T, <span class="kw1">class</span> Proj <span class="sy1">=</span> std<span class="sy4">::</span><span class="me2">identity</span>,<br /></span>
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<p> std<span class="sy4">::</span><span class="me2">indirect_strict_weak_order</span><span class="sy1"><</span><br />
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<span class="kw4">const</span> T<span class="sy2">*</span>,<br />
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std<span class="sy4">::</span><span class="me2">projected</span><span class="sy1"><</span>std<span class="sy4">::</span><span class="me2">iterator_t</span><span class="sy1"><</span>R<span class="sy1">></span>, Proj<span class="sy1">>></span> Comp <span class="sy1">=</span> ranges<span class="sy4">::</span><span class="me2">less</span> <span class="sy1">></span><br />
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<span class="kw4">constexpr</span> ranges<span class="sy4">::</span><span class="me2">borrowed_subrange_t</span><span class="sy1"><</span>R<span class="sy1">></span><br /></p>
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equal_range<span class="br0">(</span>R<span class="sy3">&&</span> r, <span class="kw4">const</span> T<span class="sy3">&</span> value, Comp comp <span class="sy1">=</span> <span class="br0">{</span><span class="br0">}</span>, Proj proj <span class="sy1">=</span> <span class="br0">{</span><span class="br0">}</span><span class="br0">)</span><span class="sy4">;</span></div>
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<td>(2)</td>
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<td><span class="t-mark-rev t-since-cxx20">(C++20 起)</span></td>
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<div class="t-li1"><span class="t-li">1)</span> 返回范围 <code>[first, last)</code> 中含有所有等价于 <code>value</code> 的元素的范围的视图。</div>
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<p>范围 <code>[first, last)</code> 必须至少相对于 <code>value</code> 有序，即它必须满足下列所有要求：</p>
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<ul>
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<li>已相对 <span class="t-c"><span class="mw-geshi cpp source-cpp">element <span class="sy1"><</span> value</span></span> 或 <span class="t-c"><span class="mw-geshi cpp source-cpp">comp<span class="br0">(</span>element, value<span class="br0">)</span></span></span> 划分（即所有令该表达式为 <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw2">true</span></span></span> 的元素必须前趋所有令此表达式为 <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw2">false</span></span></span> 的元素）</li>
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<li>已相对 <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="sy3">!</span><span class="br0">(</span>value <span class="sy1"><</span> element<span class="br0">)</span></span></span> 或 <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="sy3">!</span>comp<span class="br0">(</span>value, element<span class="br0">)</span></span></span> 划分</li>
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<li>对于所有元素，若 <span class="t-c"><span class="mw-geshi cpp source-cpp">element <span class="sy1"><</span> value</span></span> 或 <span class="t-c"><span class="mw-geshi cpp source-cpp">comp<span class="br0">(</span>element, value<span class="br0">)</span></span></span> 为 <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw2">true</span></span></span> ，则 <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="sy3">!</span><span class="br0">(</span>value <span class="sy1"><</span> element<span class="br0">)</span></span></span> 或 <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="sy3">!</span>comp<span class="br0">(</span>value, element<span class="br0">)</span></span></span> 亦为 <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw2">true</span></span></span></li>
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</ul>
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<p>完全排序的范围满足这些判别标准。</p>
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<p>返回的视图从二个迭代器构造，第一个指向首个<i>不小于</i> <code>value</code> 的元素，而第二个指向首个<i>大于</i> <code>value</code> 的元素。可替而用 <span class="t-lc">std::ranges::lower_bound()</span> 获得第一迭代器，用 <span class="t-lc">std::ranges::upper_bound()</span> 获得第二迭代器。</p>
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<div class="t-li1"><span class="t-li">2)</span> 同 <span class="t-v">(1)</span> ，但以 <code>r</code> 为源范围，如同以 <span class="t-c"><span class="mw-geshi cpp source-cpp">ranges<span class="sy4">::</span><span class="me2">begin</span><span class="br0">(</span>r<span class="br0">)</span></span></span> 为 <code>first</code> 并以 <span class="t-c"><span class="mw-geshi cpp source-cpp">ranges<span class="sy4">::</span><span class="me2">end</span><span class="br0">(</span>r<span class="br0">)</span></span></span> 为 <code>last</code> 。</div>
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<p>此页面上描述的仿函数实体是 <i>niebloid</i> ，即：</p>
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<ul>
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<li>调用它们中的任何一者时不可指定显式模板实参。</li>
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<li>它们无一对<a href="cpp-language-adl.html">实参依赖查找</a>可见。</li>
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<li>在<a href="cpp-language-unqualified_lookup.html">通常无限定查找</a>寻找函数调用运算符左侧的名称找到它们之一时，它禁止<a href="cpp-language-adl.html">实参依赖查找</a>。</li>
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</ul>
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<p>实际上，它们能以函数对象，或以某些特殊编译器扩展实现。</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>first, last</td>
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<td>-</td>
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<td>要检验的元素范围</td>
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</tr>
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<tr class="t-par">
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<td>r</td>
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<td>-</td>
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<td>要检验的元素范围</td>
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</tr>
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<tr class="t-par">
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<td>value</td>
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<td>-</td>
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<td>要比较的元素</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>第一参数是否<i>小于</i>（即先序于）第二个</td>
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</tr>
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<tr class="t-par">
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<td>proj</td>
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<td>-</td>
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<td>应用到元素的投影</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>含有定义所需范围的迭代器对的 <span class="t-lc">std::ranges::subrange</span> ，第一迭代器指向首个<i>不小于</i> <code>value</code> 的元素而第二迭代器指向首个<i>大于</i> <code>value</code> 的元素。</p>
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<p>若无元素<i>小于</i> <code>value</code> ，则返回尾迭代器（等于 <code>last</code> 或 <span class="t-c"><span class="mw-geshi cpp source-cpp">ranges<span class="sy4">::</span><span class="me2">end</span><span class="br0">(</span>r<span class="br0">)</span></span></span> 的迭代器）作为第一迭代器。类似地若无元素<i>大于</i> <code>value</code> ，则返回尾迭代器作为第二迭代器。</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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<p>进行的比较次数与 <code>first</code> 与 <code>last</code> 间的距离成对数（至多 <span class="texhtml" style="white-space: nowrap;">2 * log<span class="t-su t-su-b"><br />
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2</span>(last - first) + O(1)</span> 次比较）。然而，对于不实现 <a href="cpp-iterator-random_access_iterator.html"><code>random_access_iterator</code></a> 的迭代器，迭代器自增次数为线性。</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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<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">struct</span> equal_range_fn <span class="br0">{</span>
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<span class="kw1">template</span><span class="sy1"><</span> std<span class="sy4">::</span><span class="me2">forward_iterator</span> I, std<span class="sy4">::</span><span class="me2">sentinel_for</span><span class="sy1"><</span>I<span class="sy1">></span> S,
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<span class="kw1">class</span> T, <span class="kw1">class</span> Proj <span class="sy1">=</span> std<span class="sy4">::</span><span class="me2">identity</span>,
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std<span class="sy4">::</span><span class="me2">indirect_strict_weak_order</span><span class="sy1"><</span>
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<span class="kw4">const</span> T<span class="sy2">*</span>,
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std<span class="sy4">::</span><span class="me2">projected</span><span class="sy1"><</span>I, Proj<span class="sy1">>></span> Comp <span class="sy1">=</span> ranges<span class="sy4">::</span><span class="me2">less</span> <span class="sy1">></span>
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<span class="kw4">constexpr</span> ranges<span class="sy4">::</span><span class="me2">subrange</span><span class="sy1"><</span>I<span class="sy1">></span>
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operator<span class="br0">(</span><span class="br0">)</span><span class="br0">(</span>I first, S last, <span class="kw4">const</span> T<span class="sy3">&</span> value, Comp comp <span class="sy1">=</span> <span class="br0">{</span><span class="br0">}</span>, Proj proj <span class="sy1">=</span> <span class="br0">{</span><span class="br0">}</span><span class="br0">)</span> <span class="kw4">const</span>
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<span class="br0">{</span>
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<span class="kw1">return</span> ranges<span class="sy4">::</span><span class="me2">subrange</span><span class="br0">(</span>
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ranges<span class="sy4">::</span><span class="me2">lower_bound</span><span class="br0">(</span>first, last, value, <a href="cpp-utility-functional-ref.html"><span class="kw1069">std::<span class="me2">ref</span></span></a><span class="br0">(</span>comp<span class="br0">)</span>, <a href="cpp-utility-functional-ref.html"><span class="kw1069">std::<span class="me2">ref</span></span></a><span class="br0">(</span>proj<span class="br0">)</span><span class="br0">)</span>,
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ranges<span class="sy4">::</span><span class="me2">upper_bound</span><span class="br0">(</span>first, last, value, <a href="cpp-utility-functional-ref.html"><span class="kw1069">std::<span class="me2">ref</span></span></a><span class="br0">(</span>comp<span class="br0">)</span>, <a href="cpp-utility-functional-ref.html"><span class="kw1069">std::<span class="me2">ref</span></span></a><span class="br0">(</span>proj<span class="br0">)</span><span class="br0">)</span><span class="br0">)</span><span class="sy4">;</span>
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<span class="br0">}</span>
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<span class="kw1">template</span><span class="sy1"><</span> ranges<span class="sy4">::</span><span class="me2">forward_range</span> R, <span class="kw1">class</span> T, <span class="kw1">class</span> Proj <span class="sy1">=</span> std<span class="sy4">::</span><span class="me2">identity</span>,
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std<span class="sy4">::</span><span class="me2">indirect_strict_weak_order</span><span class="sy1"><</span>
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<span class="kw4">const</span> T<span class="sy2">*</span>,
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std<span class="sy4">::</span><span class="me2">projected</span><span class="sy1"><</span>std<span class="sy4">::</span><span class="me2">ranges</span><span class="sy4">::</span><span class="me2">iterator_t</span><span class="sy1"><</span>R<span class="sy1">></span>, Proj<span class="sy1">>></span> Comp <span class="sy1">=</span> ranges<span class="sy4">::</span><span class="me2">less</span> <span class="sy1">></span>
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<span class="kw4">constexpr</span> ranges<span class="sy4">::</span><span class="me2">borrowed_subrange_t</span><span class="sy1"><</span>R<span class="sy1">></span>
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operator<span class="br0">(</span><span class="br0">)</span><span class="br0">(</span>R<span class="sy3">&&</span> r, <span class="kw4">const</span> T<span class="sy3">&</span> value, Comp comp <span class="sy1">=</span> <span class="br0">{</span><span class="br0">}</span>, Proj proj <span class="sy1">=</span> <span class="br0">{</span><span class="br0">}</span><span class="br0">)</span> <span class="kw4">const</span>
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<span class="br0">{</span>
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<span class="kw1">return</span> <span class="br0">(</span><span class="sy2">*</span>this<span class="br0">)</span><span class="br0">(</span>ranges<span class="sy4">::</span><span class="me2">begin</span><span class="br0">(</span>r<span class="br0">)</span>, ranges<span class="sy4">::</span><span class="me2">end</span><span class="br0">(</span>r<span class="br0">)</span>, value,
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<a href="cpp-utility-functional-ref.html"><span class="kw1069">std::<span class="me2">ref</span></span></a><span class="br0">(</span>comp<span class="br0">)</span>, <a href="cpp-utility-functional-ref.html"><span class="kw1069">std::<span class="me2">ref</span></span></a><span class="br0">(</span>proj<span class="br0">)</span><span class="br0">)</span><span class="sy4">;</span>
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<span class="br0">}</span>
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<span class="br0">}</span><span class="sy4">;</span>
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<span class="kw1">inline</span> <span class="kw4">constexpr</span> equal_range_fn equal_range<span class="sy4">;</span></pre></div>
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</div>
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</td>
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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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<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 <compare></span>
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<span class="co2">#include <vector></span>
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<span class="co2">#include <iostream></span>
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<span class="kw1">struct</span> S
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<span class="br0">{</span>
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<span class="kw4">int</span> number<span class="sy4">;</span>
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<span class="kw4">char</span> name<span class="sy4">;</span>
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<span class="co1">// 注：这些比较运算符忽略名称</span>
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<span class="kw1">friend</span> <span class="kw4">bool</span> operator<span class="sy1">==</span> <span class="br0">(</span> <span class="kw4">const</span> S s1, <span class="kw4">const</span> S s2 <span class="br0">)</span> <span class="br0">{</span> <span class="kw1">return</span> s1.<span class="me1">number</span> <span class="sy1">==</span> s2.<span class="me1">number</span><span class="sy4">;</span> <span class="br0">}</span>
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<span class="kw1">friend</span> <span class="kw4">auto</span> operator<span class="sy1"><=></span> <span class="br0">(</span> <span class="kw4">const</span> S s1, <span class="kw4">const</span> S s2 <span class="br0">)</span> <span class="br0">{</span> <span class="kw1">return</span> s1.<span class="me1">number</span> <span class="sy1"><=></span> s2.<span class="me1">number</span><span class="sy4">;</span> <span class="br0">}</span>
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<span class="br0">}</span><span class="sy4">;</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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<span class="co1">// 注：非有序，仅按照定义如下的 S 划分</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>S<span class="sy1">></span> vec <span class="sy1">=</span> <span class="br0">{</span> <span class="br0">{</span><span class="nu0">1</span>,<span class="st0">'A'</span><span class="br0">}</span>, <span class="br0">{</span><span class="nu0">2</span>,<span class="st0">'B'</span><span class="br0">}</span>, <span class="br0">{</span><span class="nu0">2</span>,<span class="st0">'C'</span><span class="br0">}</span>, <span class="br0">{</span><span class="nu0">2</span>,<span class="st0">'D'</span><span class="br0">}</span>, <span class="br0">{</span><span class="nu0">4</span>, <span class="st0">'D'</span><span class="br0">}</span>, <span class="br0">{</span><span class="nu0">4</span>,<span class="st0">'G'</span><span class="br0">}</span>, <span class="br0">{</span><span class="nu0">3</span>,<span class="st0">'F'</span><span class="br0">}</span> <span class="br0">}</span><span class="sy4">;</span>
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S value <span class="sy1">=</span> <span class="br0">{</span><span class="nu0">2</span>, <span class="st0">'?'</span><span class="br0">}</span><span class="sy4">;</span>
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<span class="kw1">namespace</span> ranges <span class="sy1">=</span> std<span class="sy4">::</span><span class="me2">ranges</span><span class="sy4">;</span>
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<span class="br0">{</span>
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<span class="kw4">auto</span> p <span class="sy1">=</span> ranges<span class="sy4">::</span><span class="me2">equal_range</span><span class="br0">(</span>vec, value<span class="br0">)</span><span class="sy4">;</span>
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<span class="kw1">for</span> <span class="br0">(</span> <span class="kw4">auto</span> i <span class="sy4">:</span> p <span class="br0">)</span>
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<a href="cpp-io-cout.html"><span class="kw1758">std::<span class="me2">cout</span></span></a> <span class="sy1"><<</span> i.<span class="me1">name</span> <span class="sy1"><<</span> <span class="st0">' '</span><span class="sy4">;</span>
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<span class="br0">}</span>
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<span class="br0">{</span>
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<span class="kw4">auto</span> p <span class="sy1">=</span> ranges<span class="sy4">::</span><span class="me2">equal_range</span><span class="br0">(</span>vec.<span class="me1">begin</span><span class="br0">(</span><span class="br0">)</span>, vec.<span class="me1">end</span><span class="br0">(</span><span class="br0">)</span>, value<span class="br0">)</span><span class="sy4">;</span>
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<span class="kw1">for</span> <span class="br0">(</span> <span class="kw4">auto</span> i <span class="sy1">=</span> p.<span class="me1">begin</span><span class="br0">(</span><span class="br0">)</span><span class="sy4">;</span> i <span class="sy3">!</span><span class="sy1">=</span> p.<span class="me1">end</span><span class="br0">(</span><span class="br0">)</span><span class="sy4">;</span> <span class="sy2">++</span>i <span class="br0">)</span>
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<a href="cpp-io-cout.html"><span class="kw1758">std::<span class="me2">cout</span></span></a> <span class="sy1"><<</span> i<span class="sy2">-</span><span class="sy1">></span>name <span class="sy1"><<</span> <span class="st0">' '</span><span class="sy4">;</span>
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<span class="br0">}</span>
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<a href="cpp-io-cout.html"><span class="kw1758">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>
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<span class="kw4">auto</span> p <span class="sy1">=</span> ranges<span class="sy4">::</span><span class="me2">equal_range</span><span class="br0">(</span>vec, <span class="st0">'D'</span>, ranges<span class="sy4">::</span><span class="me2">less</span><span class="br0">{</span><span class="br0">}</span>, <span class="sy3">&</span>S<span class="sy4">::</span><span class="me2">name</span><span class="br0">)</span><span class="sy4">;</span>
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<span class="kw1">for</span> <span class="br0">(</span> <span class="kw4">auto</span> i <span class="sy4">:</span> p <span class="br0">)</span>
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<a href="cpp-io-cout.html"><span class="kw1758">std::<span class="me2">cout</span></span></a> <span class="sy1"><<</span> i.<span class="me1">name</span> <span class="sy1"><<</span> <span class="st0">' '</span><span class="sy4">;</span>
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<span class="br0">}</span>
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<span class="br0">{</span>
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<span class="kw4">auto</span> p <span class="sy1">=</span> ranges<span class="sy4">::</span><span class="me2">equal_range</span><span class="br0">(</span>vec.<span class="me1">begin</span><span class="br0">(</span><span class="br0">)</span>,vec.<span class="me1">end</span><span class="br0">(</span><span class="br0">)</span>, <span class="st0">'D'</span>, ranges<span class="sy4">::</span><span class="me2">less</span><span class="br0">{</span><span class="br0">}</span>, <span class="sy3">&</span>S<span class="sy4">::</span><span class="me2">name</span><span class="br0">)</span><span class="sy4">;</span>
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<span class="kw1">for</span> <span class="br0">(</span> <span class="kw4">auto</span> i <span class="sy1">=</span> p.<span class="me1">begin</span><span class="br0">(</span><span class="br0">)</span><span class="sy4">;</span> i <span class="sy3">!</span><span class="sy1">=</span> p.<span class="me1">end</span><span class="br0">(</span><span class="br0">)</span><span class="sy4">;</span> <span class="sy2">++</span>i <span class="br0">)</span>
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<a href="cpp-io-cout.html"><span class="kw1758">std::<span class="me2">cout</span></span></a> <span class="sy1"><<</span> i<span class="sy2">-</span><span class="sy1">></span>name <span class="sy1"><<</span> <span class="st0">' '</span><span class="sy4">;</span>
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<span class="br0">}</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">B C D B C D
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D D D D</pre></div>
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</div>
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</div>
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<p><br /></p>
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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-ranges-lower_bound.html"><span class="t-lines"><span>ranges::lower_bound</span></span></a></div>
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<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx20">(C++20)</span></span></span></div>
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</div>
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</td>
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<td>返回指向首个<i>不小于</i>给定值的元素的迭代器<br />
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<span class="t-mark">(niebloid)</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-ranges-upper_bound.html"><span class="t-lines"><span>ranges::upper_bound</span></span></a></div>
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<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx20">(C++20)</span></span></span></div>
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</div>
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</td>
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<td>返回指向首个<i>大于</i>某值的元素的迭代器<br />
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<span class="t-mark">(niebloid)</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-ranges-binary_search.html"><span class="t-lines"><span>ranges::binary_search</span></span></a></div>
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<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx20">(C++20)</span></span></span></div>
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</div>
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</td>
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<td>确定元素是否存在于某范围中<br />
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<span class="t-mark">(niebloid)</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-ranges-partition.html"><span class="t-lines"><span>ranges::partition</span></span></a></div>
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<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx20">(C++20)</span></span></span></div>
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</div>
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</td>
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<td>将范围中的元素分为二组<br />
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<span class="t-mark">(niebloid)</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-equal_range.html"><span class="t-lines"><span>equal_range</span></span></a></div>
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</div>
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</td>
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<td>返回匹配特定键值的元素范围<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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