klarkxy/hustoj
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

上传cppreference

Browse Source
This commit is contained in:
klarkxy
2025-08-01 12:57:54 +08:00
parent e29892f8cd
commit 196e706fe4
5485 changed files with 982007 additions and 3 deletions
Download Patch File Download Diff File Expand all files Collapse all files

272
web/cppreference-zh/chmhelp/cpp-algorithm-ranges-equal.html Normal file
View File

@@ -0,0 +1,272 @@
<!DOCTYPE html>
<html lang="zh" dir="ltr" class="client-nojs" xmlns="http://www.w3.org/1999/xhtml" xml:lang="zh">
<head><meta http-equiv="x-ua-compatible" content="ie=edge">
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>std::ranges::equal</title>
<link rel="stylesheet" href="ext.css" />
<link rel="stylesheet" href="site_modules.css" />
</head>
<body class="mediawiki ltr sitedir-ltr ns-0 ns-subject page-cpp_algorithm_ranges_equal skin-cppreference2 action-view cpp-navbar">
<div id="cpp-content-base">
<div id="content"><a id="top"></a>
<h1 id="firstHeading" class="firstHeading"><span style="font-size:0.7em; line-height:130%">std::ranges::</span>equal</h1>
<div id="bodyContent">
<div id="contentSub"><span class="subpages">&lt; <a href="cpp.html">cpp</a>&lrm; | <a href="cpp-algorithm.html">algorithm</a>&lrm; | <a href="cpp-algorithm-ranges.html">ranges</a></span></div>
<div id="mw-content-text" lang="zh" dir="ltr" class="mw-content-ltr" xml:lang="zh">
<table class="t-dcl-begin">
<tbody>
<tr class="t-dsc-header">
<td>
<div>&#23450;&#20041;&#20110;&#22836;&#25991;&#20214; <code><a href="cpp-header-algorithm.html">&lt;algorithm&gt;</a></code></div>
</td>
<td></td>
<td></td>
</tr>
<tr class="t-dcl-sep">
<td></td>
<td></td>
<td></td>
</tr>
<tr class="t-dcl-h">
<td>
<div>&#35843;&#29992;&#31614;&#21517;</div>
</td>
<td></td>
<td></td>
</tr>
<tr class="t-dcl t-since-cxx20">
<td>
<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1">&lt;</span> std<span class="sy4">::</span><span class="me2">input_iterator</span> I1, std<span class="sy4">::</span><span class="me2">sentinel_for</span><span class="sy1">&lt;</span>I1<span class="sy1">&gt;</span> S1,<br /></span>
<p>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; std<span class="sy4">::</span><span class="me2">input_iterator</span> I2, std<span class="sy4">::</span><span class="me2">sentinel_for</span><span class="sy1">&lt;</span>I2<span class="sy1">&gt;</span> S2,<br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <span class="kw1">class</span> Pred <span class="sy1">=</span> ranges<span class="sy4">::</span><span class="me2">equal_to</span>,<br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <span class="kw1">class</span> Proj1 <span class="sy1">=</span> std<span class="sy4">::</span><span class="me2">identity</span>, <span class="kw1">class</span> Proj2 <span class="sy1">=</span> std<span class="sy4">::</span><span class="me2">identity</span> <span class="sy1">&gt;</span><br />
&nbsp; requires std<span class="sy4">::</span><span class="me2">indirectly_comparable</span><span class="sy1">&lt;</span>I1, I2, Pred, Proj1, Proj2<span class="sy1">&gt;</span><br />
<span class="kw4">constexpr</span> <span class="kw4">bool</span> equal<span class="br0">(</span> I1 first1, S1 last1, I2 first2, S2 last2,<br /></p>
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Pred pred <span class="sy1">=</span> <span class="br0">{</span><span class="br0">}</span>, Proj1 proj1 <span class="sy1">=</span> <span class="br0">{</span><span class="br0">}</span>, Proj2 proj2 <span class="sy1">=</span> <span class="br0">{</span><span class="br0">}</span> <span class="br0">)</span><span class="sy4">;</span></div>
</td>
<td>(1)</td>
<td><span class="t-mark-rev t-since-cxx20">(C++20 &#36215;)</span></td>
</tr>
<tr class="t-dcl t-since-cxx20">
<td>
<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1">&lt;</span> ranges<span class="sy4">::</span><span class="me2">input_range</span> R1, ranges<span class="sy4">::</span><span class="me2">input_range</span> R2,<br /></span>
<p>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <span class="kw1">class</span> Pred <span class="sy1">=</span> ranges<span class="sy4">::</span><span class="me2">equal_to</span>,<br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <span class="kw1">class</span> Proj1 <span class="sy1">=</span> std<span class="sy4">::</span><span class="me2">identity</span>, <span class="kw1">class</span> Proj2 <span class="sy1">=</span> std<span class="sy4">::</span><span class="me2">identity</span> <span class="sy1">&gt;</span><br />
&nbsp; requires std<span class="sy4">::</span><span class="me2">indirectly_comparable</span><span class="sy1">&lt;</span>ranges<span class="sy4">::</span><span class="me2">iterator_t</span><span class="sy1">&lt;</span>R1<span class="sy1">&gt;</span>, ranges<span class="sy4">::</span><span class="me2">iterator_t</span><span class="sy1">&lt;</span>R2<span class="sy1">&gt;</span>,<br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Pred, Proj1, Proj2<span class="sy1">&gt;</span><br />
<span class="kw4">constexpr</span> <span class="kw4">bool</span> equal<span class="br0">(</span> R1<span class="sy3">&amp;&amp;</span> r1, R2<span class="sy3">&amp;&amp;</span> r2, Pred pred <span class="sy1">=</span> <span class="br0">{</span><span class="br0">}</span>,<br /></p>
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Proj1 proj1 <span class="sy1">=</span> <span class="br0">{</span><span class="br0">}</span>, Proj2 proj2 <span class="sy1">=</span> <span class="br0">{</span><span class="br0">}</span> <span class="br0">)</span><span class="sy4">;</span></div>
</td>
<td>(2)</td>
<td><span class="t-mark-rev t-since-cxx20">(C++20 &#36215;)</span></td>
</tr>
<tr class="t-dcl-sep">
<td></td>
<td></td>
<td></td>
</tr>
</tbody>
</table>
<div class="t-li1"><span class="t-li">1)</span> &#33509;&#33539;&#22260; <code>[first1, last1)</code> &#30340;&#34987;&#25237;&#24433;&#20540;&#31561;&#20110;&#33539;&#22260; <code>[first2, last2)</code> &#30340;&#34987;&#25237;&#24433;&#20540;&#21017;&#36820;&#22238; <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw2">true</span></span></span> &#65292;&#21542;&#21017;&#36820;&#22238; <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw2">false</span></span></span> &#12290;</div>
<div class="t-li1"><span class="t-li">2)</span> &#21516; <span class="t-v">(1)</span> &#65292;&#20294;&#20197; <code>r</code> &#20026;&#28304;&#33539;&#22260;&#65292;&#22914;&#21516;&#20197; <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> &#20026; <code>first</code> &#24182;&#20197; <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> &#20026; <code>last</code> &#12290;</div>
<p>&#33509;&#20108;&#20010;&#33539;&#22260;&#25317;&#26377;&#30456;&#21516;&#25968;&#37327;&#30340;&#20803;&#32032;&#65292;&#19988;&#27599;&#23545;&#34987;&#25237;&#24433;&#20803;&#32032;&#37117;&#28385;&#36275; <code>pred</code> &#65292;&#21017;&#35748;&#20026;&#23427;&#20204;&#30456;&#31561;&#65292;&#21363; <span class="t-c"><span class="mw-geshi cpp source-cpp"><a href="cpp-utility-functional-invoke.html"><span class="kw1058">std::<span class="me2">invoke</span></span></a><span class="br0">(</span>pred, <a href="cpp-utility-functional-invoke.html"><span class="kw1058">std::<span class="me2">invoke</span></span></a><span class="br0">(</span>proj1, <span class="sy2">*</span>first1<span class="br0">)</span>, <a href="cpp-utility-functional-invoke.html"><span class="kw1058">std::<span class="me2">invoke</span></span></a><span class="br0">(</span>proj2, <span class="sy2">*</span>first2<span class="br0">)</span><span class="br0">)</span></span></span> &#23545;&#33539;&#22260;&#20013;&#30340;&#25152;&#26377;&#23545;&#24212;&#20803;&#32032;&#23545;&#37117;&#36820;&#22238; <code>true</code> &#12290;</p>
<p>&#27492;&#39029;&#38754;&#19978;&#25551;&#36848;&#30340;&#20223;&#20989;&#25968;&#23454;&#20307;&#26159; <i>niebloid</i> &#65292;&#21363;&#65306;</p>
<ul>
<li>&#35843;&#29992;&#23427;&#20204;&#20013;&#30340;&#20219;&#20309;&#19968;&#32773;&#26102;&#19981;&#21487;&#25351;&#23450;&#26174;&#24335;&#27169;&#26495;&#23454;&#21442;&#12290;</li>
<li>&#23427;&#20204;&#26080;&#19968;&#23545;<a href="cpp-language-adl.html">&#23454;&#21442;&#20381;&#36182;&#26597;&#25214;</a>&#21487;&#35265;&#12290;</li>
<li>&#22312;<a href="cpp-language-unqualified_lookup.html">&#36890;&#24120;&#26080;&#38480;&#23450;&#26597;&#25214;</a>&#23547;&#25214;&#20989;&#25968;&#35843;&#29992;&#36816;&#31639;&#31526;&#24038;&#20391;&#30340;&#21517;&#31216;&#25214;&#21040;&#23427;&#20204;&#20043;&#19968;&#26102;&#65292;&#23427;&#31105;&#27490;<a href="cpp-language-adl.html">&#23454;&#21442;&#20381;&#36182;&#26597;&#25214;</a>&#12290;</li>
</ul>
<p>&#23454;&#38469;&#19978;&#65292;&#23427;&#20204;&#33021;&#20197;&#20989;&#25968;&#23545;&#35937;&#65292;&#25110;&#20197;&#26576;&#20123;&#29305;&#27530;&#32534;&#35793;&#22120;&#25193;&#23637;&#23454;&#29616;&#12290;</p>
<h3><span class="mw-headline" id=".E5.8F.82.E6.95.B0">&#21442;&#25968;</span></h3>
<table class="t-par-begin">
<tr class="t-par">
<td>first1, last1</td>
<td>-</td>
<td>&#23450;&#20041;&#35201;&#27604;&#36739;&#30340;&#31532;&#19968;&#20803;&#32032;&#33539;&#22260;&#30340;&#36845;&#20195;&#22120;-&#21736;&#20301;&#23545;</td>
</tr>
<tr class="t-par">
<td>r1</td>
<td>-</td>
<td>&#35201;&#27604;&#36739;&#30340;&#31532;&#19968;&#20803;&#32032;&#33539;&#22260;</td>
</tr>
<tr class="t-par">
<td>first2, last2</td>
<td>-</td>
<td>&#23450;&#20041;&#35201;&#27604;&#36739;&#30340;&#31532;&#19968;&#20803;&#32032;&#33539;&#22260;&#30340;&#36845;&#20195;&#22120;-&#21736;&#20301;&#23545;</td>
</tr>
<tr class="t-par">
<td>r2</td>
<td>-</td>
<td>&#35201;&#27604;&#36739;&#30340;&#31532;&#20108;&#20803;&#32032;&#33539;&#22260;</td>
</tr>
<tr class="t-par">
<td>pred</td>
<td>-</td>
<td>&#24212;&#29992;&#21040;&#25237;&#24433;&#21518;&#20803;&#32032;&#30340;&#35859;&#35789;</td>
</tr>
<tr class="t-par">
<td>proj1</td>
<td>-</td>
<td>&#24212;&#29992;&#21040;&#31532;&#19968;&#20803;&#32032;&#33539;&#22260;&#30340;&#25237;&#24433;</td>
</tr>
<tr class="t-par">
<td>proj2</td>
<td>-</td>
<td>&#24212;&#29992;&#21040;&#31532;&#20108;&#20803;&#32032;&#33539;&#22260;&#30340;&#25237;&#24433;</td>
</tr>
</table>
<h3><span class="mw-headline" id=".E8.BF.94.E5.9B.9E.E5.80.BC">&#36820;&#22238;&#20540;</span></h3>
<p>&#33509;&#33539;&#22260; <code>[first1, last1)</code> &#30340;&#38271;&#24230;&#19981;&#31561;&#20110;&#33539;&#22260; <code>[first2, last2)</code> &#30340;&#38271;&#24230;&#65292;&#21017;&#36820;&#22238; <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw2">false</span></span></span> &#12290;</p>
<p>&#33509;&#20108;&#20010;&#33539;&#22260;&#20013;&#30340;&#20803;&#32032;&#22312;&#25237;&#24433;&#21518;&#30456;&#31561;&#65292;&#21017;&#36820;&#22238; <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw2">true</span></span></span> &#12290;</p>
<p>&#21542;&#21017;&#36820;&#22238; <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw2">false</span></span></span> &#12290;</p>
<h3><span class="mw-headline" id=".E6.B3.A8.E8.A7.A3">&#27880;&#35299;</span></h3>
<p>&#19981;&#24212;&#29992; <code>ranges::equal</code> &#27604;&#36739;&#30001;&#26469;&#33258; <span class="t-lc"><a href="cpp-container-unordered_set.html">std::unordered_set</a></span> &#12289; <span class="t-lc"><a href="cpp-container-unordered_multiset.html">std::unordered_multiset</a></span> &#12289; <span class="t-lc"><a href="cpp-container-unordered_map.html">std::unordered_map</a></span> &#25110; <span class="t-lc"><a href="cpp-container-unordered_multimap.html">std::unordered_multimap</a></span> &#30340;&#36845;&#20195;&#22120;&#32452;&#25104;&#30340;&#33539;&#22260;&#65292;&#22240;&#20026;&#21363;&#20351;&#20108;&#20010;&#23481;&#22120;&#23384;&#20648;&#30456;&#21516;&#20803;&#32032;&#65292;&#20803;&#32032;&#22312;&#23481;&#22120;&#20013;&#30340;&#23384;&#20648;&#39034;&#24207;&#20134;&#21487;&#20197;&#30456;&#24322;&#12290;</p>
<p>&#27604;&#36739;&#25972;&#20010;&#23481;&#22120;&#30456;&#31561;&#26102;&#65292;&#36890;&#24120;&#20559;&#22909;&#23545;&#24212;&#23481;&#22120;&#30340; <code>operator==</code> &#12290;</p>
<h3><span class="mw-headline" id=".E5.A4.8D.E6.9D.82.E5.BA.A6">&#22797;&#26434;&#24230;</span></h3>
<p>&#33267;&#22810;&#24212;&#29992; min(<code>last1</code> - <code>first1</code>, <code>last2</code> - <code>first2</code>) &#27425;&#35859;&#35789;&#21644;&#23545;&#24212;&#30340;&#25237;&#24433;&#12290;</p>
<p>&#28982;&#32780;&#65292;&#33509; <code>S1</code> &#19982; <code>S2</code> &#22343;&#20998;&#21035;&#19982;&#20854;&#36845;&#20195;&#22120;&#23454;&#29616; <span class="t-lc">std::sized_sentinel_for</span> &#65292;&#19988; <span class="t-c"><span class="mw-geshi cpp source-cpp">last1 <span class="sy2">-</span> first1 <span class="sy3">!</span><span class="sy1">=</span> last2 <span class="sy2">-</span> first2</span></span> &#65292;&#21017;&#19981;&#24212;&#29992;&#35859;&#35789;&#65288;&#26080;&#38656;&#26597;&#30475;&#20219;&#20309;&#20803;&#32032;&#21363;&#21487;&#26816;&#27979;&#20986;&#22823;&#23567;&#19981;&#21512;&#65289;&#12290;</p>
<h3><span class="mw-headline" id=".E5.8F.AF.E8.83.BD.E7.9A.84.E5.AE.9E.E7.8E.B0">&#21487;&#33021;&#30340;&#23454;&#29616;</span></h3>
<table class="eq-fun-cpp-table">
<tr>
<td>
<div dir="ltr" class="mw-geshi" style="text-align: left;">
<div class="cpp source-cpp">
<pre class="de1"><span class="kw1">struct</span> equal_fn <span class="br0">{</span>
<span class="kw1">template</span><span class="sy1">&lt;</span>std<span class="sy4">::</span><span class="me2">input_iterator</span> I1, std<span class="sy4">::</span><span class="me2">sentinel_for</span><span class="sy1">&lt;</span>I1<span class="sy1">&gt;</span> S1,
std<span class="sy4">::</span><span class="me2">input_iterator</span> I2, std<span class="sy4">::</span><span class="me2">sentinel_for</span><span class="sy1">&lt;</span>I2<span class="sy1">&gt;</span> S2,
<span class="kw1">class</span> Pred <span class="sy1">=</span> ranges<span class="sy4">::</span><span class="me2">equal_to</span>,
<span class="kw1">class</span> Proj1 <span class="sy1">=</span> std<span class="sy4">::</span><span class="me2">identity</span>, <span class="kw1">class</span> Proj2 <span class="sy1">=</span> std<span class="sy4">::</span><span class="me2">identity</span><span class="sy1">&gt;</span>
requires std<span class="sy4">::</span><span class="me2">indirectly_comparable</span><span class="sy1">&lt;</span>I1, I2, Pred, Proj1, Proj2<span class="sy1">&gt;</span>
<span class="kw4">constexpr</span> <span class="kw4">bool</span>
operator<span class="br0">(</span><span class="br0">)</span><span class="br0">(</span>I1 first1, S1 last1, I2 first2, S2 last2,
Pred pred <span class="sy1">=</span> <span class="br0">{</span><span class="br0">}</span>, Proj1 proj1 <span class="sy1">=</span> <span class="br0">{</span><span class="br0">}</span>, Proj2 proj2 <span class="sy1">=</span> <span class="br0">{</span><span class="br0">}</span><span class="br0">)</span> <span class="kw4">const</span>
<span class="br0">{</span>
<span class="kw1">if</span> <span class="br0">(</span>ranges<span class="sy4">::</span><span class="me2">distance</span><span class="br0">(</span>first1, last1<span class="br0">)</span> <span class="sy3">!</span><span class="sy1">=</span> ranges<span class="sy4">::</span><span class="me2">distance</span><span class="br0">(</span>first2, last2<span class="br0">)</span><span class="br0">)</span> <span class="br0">{</span>
<span class="kw1">return</span> <span class="kw2">false</span><span class="sy4">;</span>
<span class="br0">}</span>
<span class="kw1">for</span> <span class="br0">(</span><span class="sy4">;</span> first1 <span class="sy3">!</span><span class="sy1">=</span> last1<span class="sy4">;</span> <span class="sy2">++</span>first1, <span class="br0">(</span><span class="kw4">void</span><span class="br0">)</span><span class="sy2">++</span>first2<span class="br0">)</span> <span class="br0">{</span>
<span class="kw1">if</span> <span class="br0">(</span><span class="sy3">!</span><a href="cpp-utility-functional-invoke.html"><span class="kw1058">std::<span class="me2">invoke</span></span></a><span class="br0">(</span>pred, <a href="cpp-utility-functional-invoke.html"><span class="kw1058">std::<span class="me2">invoke</span></span></a><span class="br0">(</span>proj1, <span class="sy2">*</span>first1<span class="br0">)</span>, <a href="cpp-utility-functional-invoke.html"><span class="kw1058">std::<span class="me2">invoke</span></span></a><span class="br0">(</span>proj2, <span class="sy2">*</span>first2<span class="br0">)</span><span class="br0">)</span><span class="br0">)</span> <span class="br0">{</span>
<span class="kw1">return</span> <span class="kw2">false</span><span class="sy4">;</span>
<span class="br0">}</span>
<span class="br0">}</span>
<span class="kw1">return</span> <span class="kw2">true</span><span class="sy4">;</span>
<span class="br0">}</span>
<span class="kw1">template</span><span class="sy1">&lt;</span>ranges<span class="sy4">::</span><span class="me2">input_range</span> R1, std<span class="sy4">::</span><span class="me2">input_range</span> R2,
<span class="kw1">class</span> Pred <span class="sy1">=</span> ranges<span class="sy4">::</span><span class="me2">equal_to</span>,
<span class="kw1">class</span> Proj1 <span class="sy1">=</span> std<span class="sy4">::</span><span class="me2">identity</span>, <span class="kw1">class</span> Proj2 <span class="sy1">=</span> std<span class="sy4">::</span><span class="me2">identity</span><span class="sy1">&gt;</span>
requires std<span class="sy4">::</span><span class="me2">indirectly_comparable</span><span class="sy1">&lt;</span>ranges<span class="sy4">::</span><span class="me2">iterator_t</span><span class="sy1">&lt;</span>R1<span class="sy1">&gt;</span>, ranges<span class="sy4">::</span><span class="me2">iterator_t</span><span class="sy1">&lt;</span>R2<span class="sy1">&gt;</span>,
Pred, Proj1, Proj2<span class="sy1">&gt;</span>
<span class="kw4">constexpr</span> <span class="kw4">bool</span>
operator<span class="br0">(</span><span class="br0">)</span><span class="br0">(</span>R1<span class="sy3">&amp;&amp;</span> r1, R2<span class="sy3">&amp;&amp;</span> r2, Pred pred <span class="sy1">=</span> <span class="br0">{</span><span class="br0">}</span>, Proj1 proj1 <span class="sy1">=</span> <span class="br0">{</span><span class="br0">}</span>, Proj2 proj2 <span class="sy1">=</span> <span class="br0">{</span><span class="br0">}</span><span class="br0">)</span> <span class="kw4">const</span>
<span class="br0">{</span>
<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>r1<span class="br0">)</span>, ranges<span class="sy4">::</span><span class="me2">end</span><span class="br0">(</span>r1<span class="br0">)</span>,
ranges<span class="sy4">::</span><span class="me2">begin</span><span class="br0">(</span>r2<span class="br0">)</span>, ranges<span class="sy4">::</span><span class="me2">end</span><span class="br0">(</span>r2<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>pred<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>proj1<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>proj2<span class="br0">)</span><span class="br0">)</span><span class="sy4">;</span>
<span class="br0">}</span>
<span class="br0">}</span><span class="sy4">;</span>
<span class="kw1">inline</span> <span class="kw4">constexpr</span> equal_fn equal<span class="sy4">;</span></pre></div>
</div>
</td>
</tr>
</table>
<h3><span class="mw-headline" id=".E7.A4.BA.E4.BE.8B">&#31034;&#20363;</span></h3>
<div class="t-example">
<p>&#19979;&#21015;&#20195;&#30721;&#29992; <code>equal()</code> &#27979;&#35797;&#23383;&#31526;&#20018;&#26159;&#21542;&#20026;&#22238;&#25991;</p>
<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 &lt;algorithm&gt;</span>
<span class="co2">#include &lt;iostream&gt;</span>
<span class="co2">#include &lt;string_view&gt;</span>
<span class="co2">#include &lt;ranges&gt;</span>
<span class="kw4">bool</span> is_palindrome<span class="br0">(</span><span class="kw4">const</span> <a href="cpp-string-basic_string_view.html"><span class="kw1248">std::<span class="me2">string_view</span></span></a> s<span class="br0">)</span>
<span class="br0">{</span>
<span class="kw1">namespace</span> views <span class="sy1">=</span> std<span class="sy4">::</span><span class="me2">views</span><span class="sy4">;</span>
<span class="kw4">auto</span> forward <span class="sy1">=</span> s <span class="sy3">|</span> views<span class="sy4">::</span><span class="me2">take</span><span class="br0">(</span>s.<span class="me1">size</span><span class="br0">(</span><span class="br0">)</span> <span class="sy2">/</span> <span class="nu0">2</span><span class="br0">)</span><span class="sy4">;</span>
<span class="kw4">auto</span> backward <span class="sy1">=</span> s <span class="sy3">|</span> views<span class="sy4">::</span><span class="me2">reverse</span> <span class="sy3">|</span> views<span class="sy4">::</span><span class="me2">take</span><span class="br0">(</span>s.<span class="me1">size</span><span class="br0">(</span><span class="br0">)</span> <span class="sy2">/</span> <span class="nu0">2</span><span class="br0">)</span><span class="sy4">;</span>
<span class="kw1">return</span> std<span class="sy4">::</span><span class="me2">ranges</span><span class="sy4">::</span><span class="me2">equal</span><span class="br0">(</span>forward, backward<span class="br0">)</span><span class="sy4">;</span>
<span class="br0">}</span>
<span class="kw4">void</span> test<span class="br0">(</span><span class="kw4">const</span> <a href="cpp-string-basic_string_view.html"><span class="kw1248">std::<span class="me2">string_view</span></span></a> s<span class="br0">)</span>
<span class="br0">{</span>
<a href="cpp-io-cout.html"><span class="kw1758">std::<span class="me2">cout</span></span></a> <span class="sy1">&lt;&lt;</span> <span class="st0">&quot;<span class="es1">\&quot;</span>&quot;</span> <span class="sy1">&lt;&lt;</span> s <span class="sy1">&lt;&lt;</span> <span class="st0">&quot;<span class="es1">\&quot;</span> is&quot;</span>
<span class="sy1">&lt;&lt;</span> <span class="br0">(</span>is_palindrome<span class="br0">(</span>s<span class="br0">)</span> <span class="sy4">?</span> <span class="st0">&quot;&quot;</span> <span class="sy4">:</span> <span class="st0">&quot;not&quot;</span><span class="br0">)</span>
<span class="sy1">&lt;&lt;</span> <span class="st0">&quot; a palindrome<span class="es1">\n</span>&quot;</span><span class="sy4">;</span>
<span class="br0">}</span>
<span class="kw4">int</span> main<span class="br0">(</span><span class="br0">)</span>
<span class="br0">{</span>
test<span class="br0">(</span><span class="st0">&quot;radar&quot;</span><span class="br0">)</span><span class="sy4">;</span>
test<span class="br0">(</span><span class="st0">&quot;hello&quot;</span><span class="br0">)</span><span class="sy4">;</span>
<span class="br0">}</span></pre></div>
</div>
<p>&#36755;&#20986;&#65306;</p>
<div dir="ltr" class="mw-geshi" style="text-align: left;">
<div class="text source-text">
<pre class="de1">&quot;radar&quot; is a palindrome
&quot;hello&quot; is not a palindrome</pre></div>
</div>
</div>
<h3><span class="mw-headline" id=".E5.8F.82.E9.98.85">&#21442;&#38405;</span></h3>
<table class="t-dsc-begin">
<tr class="t-dsc">
<td>
<div class="t-dsc-member-div">
<div><a href="cpp-algorithm-ranges-find.html"><span class="t-lines"><span>ranges::find</span><span>ranges::find_if</span><span>ranges::find_if_not</span></span></a></div>
<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx20">(C++20)</span></span><span><span class="t-mark-rev t-since-cxx20">(C++20)</span></span><span><span class="t-mark-rev t-since-cxx20">(C++20)</span></span></span></div>
</div>
</td>
<td>&#23547;&#25214;&#39318;&#20010;&#28385;&#36275;&#29305;&#23450;&#21028;&#21035;&#26631;&#20934;&#30340;&#20803;&#32032;<br />
<span class="t-mark">(niebloid)</span></td>
</tr>
<tr class="t-dsc">
<td>
<div class="t-dsc-member-div">
<div><a href="cpp-algorithm-ranges-lexicographical_compare.html"><span class="t-lines"><span>ranges::lexicographical_compare</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>&#24403;&#19968;&#20010;&#33539;&#22260;&#25353;&#23383;&#20856;&#39034;&#24207;&#23567;&#20110;&#21478;&#19968;&#20010;&#33539;&#22260;&#26102;&#65292;&#36820;&#22238; true<br />
<span class="t-mark">(niebloid)</span></td>
</tr>
<tr class="t-dsc">
<td>
<div class="t-dsc-member-div">
<div><a href="cpp-algorithm-ranges-mismatch.html"><span class="t-lines"><span>ranges::mismatch</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>&#23547;&#25214;&#20004;&#20010;&#33539;&#22260;&#20986;&#29616;&#19981;&#21516;&#30340;&#39318;&#20010;&#20301;&#32622;<br />
<span class="t-mark">(niebloid)</span></td>
</tr>
<tr class="t-dsc">
<td>
<div class="t-dsc-member-div">
<div><a href="cpp-algorithm-ranges-search.html"><span class="t-lines"><span>ranges::search</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>&#25628;&#32034;&#19968;&#20010;&#20803;&#32032;&#33539;&#22260;<br />
<span class="t-mark">(niebloid)</span></td>
</tr>
<tr class="t-dsc">
<td>
<div class="t-dsc-member-div">
<div><a href="cpp-algorithm-equal.html"><span class="t-lines"><span>equal</span></span></a></div>
</div>
</td>
<td>&#30830;&#23450;&#20004;&#20010;&#20803;&#32032;&#38598;&#21512;&#26159;&#21542;&#26159;&#30456;&#21516;&#30340;<br />
<span class="t-mark">(&#20989;&#25968;&#27169;&#26495;)</span></td>
</tr>
</table>
</div>
<div class="visualClear"></div>
</div>
</div>
</div>
</body>
</html>