Files
hustoj/web/cppreference-zh/chmhelp/cpp-algorithm-ranges-unique.html
2025-08-01 12:57:54 +08:00

278 lines
30 KiB
HTML

<!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::unique</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_unique 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>unique</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">permutable</span> I, std<span class="sy4">::</span><span class="me2">sentinel_for</span><span class="sy1">&lt;</span>I<span class="sy1">&gt;</span> S, <span class="kw1">class</span> Proj <span class="sy1">=</span> std<span class="sy4">::</span><span class="me2">identity</span>,<br /></span>
<p>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; std<span class="sy4">::</span><span class="me2">indirect_equivalence_relation</span><span class="sy1">&lt;</span>std<span class="sy4">::</span><span class="me2">projected</span><span class="sy1">&lt;</span>I, Proj<span class="sy1">&gt;&gt;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; C <span class="sy1">=</span> ranges<span class="sy4">::</span><span class="me2">equal_to</span> <span class="sy1">&gt;</span><br />
<span class="kw4">constexpr</span> ranges<span class="sy4">::</span><span class="me2">subrange</span><span class="sy1">&lt;</span>I<span class="sy1">&gt;</span><br /></p>
unique<span class="br0">(</span> I first, S last, C 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>
</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">forward_range</span> R, <span class="kw1">class</span> Proj <span class="sy1">=</span> std<span class="sy4">::</span><span class="me2">identity</span>,<br /></span>
<p>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; std<span class="sy4">::</span><span class="me2">indirect_equivalence_relation</span><span class="sy1">&lt;</span>std<span class="sy4">::</span><span class="me2">projected</span><span class="sy1">&lt;</span>ranges<span class="sy4">::</span><span class="me2">iterator_t</span><span class="sy1">&lt;</span>R<span class="sy1">&gt;</span>, Proj<span class="sy1">&gt;&gt;</span><br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; C <span class="sy1">=</span> ranges<span class="sy4">::</span><span class="me2">equal_to</span> <span class="sy1">&gt;</span><br />
requires &nbsp;std<span class="sy4">::</span><span class="me2">permutable</span><span class="sy1">&lt;</span>ranges<span class="sy4">::</span><span class="me2">iterator_t</span><span class="sy1">&lt;</span>R<span class="sy1">&gt;&gt;</span><br />
<span class="kw4">constexpr</span> ranges<span class="sy4">::</span><span class="me2">borrowed_subrange_t</span><span class="sy1">&lt;</span>R<span class="sy1">&gt;</span><br /></p>
unique<span class="br0">(</span> R<span class="sy3">&amp;&amp;</span> r, C 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>
</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> &#20174;&#26469;&#33258;&#33539;&#22260; <code>[first, last)</code> &#30340;&#27599;&#20010;&#36830;&#32493;&#30340;&#31561;&#20215;&#20803;&#32032;&#32452;&#28040;&#38500;&#39318;&#20010;&#20197;&#22806;&#30340;&#20840;&#37096;&#20803;&#32032;&#65292;&#24182;&#36820;&#22238;&#23376;&#33539;&#22260; <code>[ret, last)</code> &#65292;&#20854;&#20013; <code>ret</code> &#26159;&#26032;&#33539;&#22260;&#30340;&#23614;&#21518;&#36845;&#20195;&#22120;&#12290;</div>
<div class="t-li1"><span class="t-li"></span> &#33509; <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>comp, <a href="cpp-utility-functional-invoke.html"><span class="kw1058">std::<span class="me2">invoke</span></span></a><span class="br0">(</span>proj, <span class="sy2">*</span><span class="br0">(</span>i <span class="sy2">-</span> <span class="nu0">1</span><span class="br0">)</span><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>proj, <span class="sy2">*</span>i<span class="br0">)</span><span class="br0">)</span> <span class="sy1">==</span> <span class="kw2">true</span></span></span> &#21017;&#35748;&#20026;&#20108;&#20010;&#36830;&#32493;&#20803;&#32032; <code>*(i - 1)</code> &#19982; <code>*i</code> &#31561;&#20215;&#65292;&#20854;&#20013; <code>i</code> &#26159;&#33539;&#22260; <code>[first + 1, last)</code> &#20013;&#30340;&#36845;&#20195;&#22120;&#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;&#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>&#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>first, last</td>
<td>-</td>
<td>&#35201;&#22788;&#29702;&#30340;&#20803;&#32032;&#33539;&#22260;</td>
</tr>
<tr class="t-par">
<td>r</td>
<td>-</td>
<td>&#35201;&#22788;&#29702;&#30340;&#20803;&#32032;&#33539;&#22260;</td>
</tr>
<tr class="t-par">
<td>comp</td>
<td>-</td>
<td>&#27604;&#36739;&#25237;&#24433;&#21518;&#20803;&#32032;&#30340;&#20108;&#20803;&#35859;&#35789;</td>
</tr>
<tr class="t-par">
<td>proj</td>
<td>-</td>
<td>&#24212;&#29992;&#21040;&#20803;&#32032;&#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>&#36820;&#22238; <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="br0">{</span>ret, last<span class="br0">}</span></span></span> &#65292;&#20854;&#20013; <code>ret</code> &#26159;&#26032;&#33539;&#22260;&#26411;&#23614;&#30340;&#23614;&#21518;&#36845;&#20195;&#22120;&#12290;</p>
<h3><span class="mw-headline" id=".E5.A4.8D.E6.9D.82.E5.BA.A6">&#22797;&#26434;&#24230;</span></h3>
<p>&#23545;&#20110;&#38750;&#31354;&#33539;&#22260;&#65292;&#20934;&#30830;&#24212;&#29992; <span class="t-c"><span class="mw-geshi cpp source-cpp">ranges<span class="sy4">::</span><span class="me2">distance</span><span class="br0">(</span>first, last<span class="br0">)</span> <span class="sy2">-</span> <span class="nu0">1</span></span></span> &#27425;&#30456;&#24212;&#30340;&#35859;&#35789; <code>comp</code> &#65292;&#24182;&#19988;&#24212;&#29992;&#25237;&#24433; <code>proj</code> &#30340;&#27425;&#25968;&#19981;&#22810;&#20110;&#20854;&#20108;&#20493;&#12290;</p>
<h3><span class="mw-headline" id=".E6.B3.A8.E8.A7.A3">&#27880;&#35299;</span></h3>
<p>&#30001;&#36801;&#31227;&#65288;&#36890;&#36807;&#31227;&#21160;&#36171;&#20540;&#30340;&#25163;&#27573;&#65289;&#33539;&#22260;&#20013;&#30340;&#20803;&#32032;&#36827;&#34892;&#31227;&#38500;&#65292;&#20351;&#24471;&#26410;&#34987;&#31227;&#38500;&#30340;&#20803;&#32032;&#20986;&#29616;&#22312;&#33539;&#22260;&#36215;&#22987;&#12290;&#20445;&#25345;&#20803;&#32032;&#30340;&#30456;&#23545;&#39034;&#24207;&#24182;&#19988;&#19981;&#25913;&#21464;&#23481;&#22120;&#30340;<i>&#29289;&#29702;</i>&#22823;&#23567;&#12290; <code>[ret, last)</code> &#20013;&#30340;&#36845;&#20195;&#22120;&#65288;&#33509;&#23384;&#22312;&#65289;&#20173;&#28982;&#21487;&#35299;&#24341;&#29992;&#65292;&#20294;&#20803;&#32032;&#33258;&#36523;&#25317;&#26377;&#26410;&#25351;&#23450;&#20540;&#65288;&#22914;<a href="cpp-named_req-MoveAssignable.html"><span style="font-style:italic">&#21487;&#31227;&#21160;&#36171;&#20540;</span> <span style="font-family: Georgia, &#39;DejaVu Serif&#39;, serif; font-style:italic">(MoveAssignable)</span></a> &#21518;&#26465;&#20214;&#25152;&#35201;&#27714;&#65289;&#12290;</p>
<p>&#23545; <code>ranges::unique</code> &#30340;&#35843;&#29992;&#26377;&#26102;&#21518;&#38543;&#23481;&#22120;&#30340; <code>erase</code> &#25104;&#21592;&#20989;&#25968;&#65292;&#36825;&#25830;&#38500;&#26410;&#25351;&#23450;&#20540;&#24182;&#20943;&#23569;&#23481;&#22120;&#30340;<i>&#29289;&#29702;</i>&#22823;&#23567;&#20197;&#21305;&#37197;&#20854;&#26032;&#30340;<i>&#36923;&#36753;</i>&#22823;&#23567;&#12290;&#27492;&#20108;&#35843;&#29992;&#19968;&#24182;&#23454;&#29616;<a href="https://en.wikipedia.org/wiki/Erase-remove_idiom" class="extiw" title="enwiki:Erase-remove idiom"><i>&#25830;&#38500;-&#31227;&#38500;</i>&#25163;&#27861;</a>&#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> unique_fn <span class="br0">{</span>
<span class="kw1">template</span><span class="sy1">&lt;</span>std<span class="sy4">::</span><span class="me2">permutable</span> I, std<span class="sy4">::</span><span class="me2">sentinel_for</span><span class="sy1">&lt;</span>I<span class="sy1">&gt;</span> S, <span class="kw1">class</span> Proj <span class="sy1">=</span> std<span class="sy4">::</span><span class="me2">identity</span>,
std<span class="sy4">::</span><span class="me2">indirect_equivalence_relation</span><span class="sy1">&lt;</span>std<span class="sy4">::</span><span class="me2">projected</span><span class="sy1">&lt;</span>I, Proj<span class="sy1">&gt;&gt;</span> C <span class="sy1">=</span> ranges<span class="sy4">::</span><span class="me2">equal_to</span><span class="sy1">&gt;</span>
<span class="kw4">constexpr</span> ranges<span class="sy4">::</span><span class="me2">subrange</span><span class="sy1">&lt;</span>I<span class="sy1">&gt;</span>
operator<span class="br0">(</span><span class="br0">)</span> <span class="br0">(</span> I first, S last, C 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> <span class="br0">{</span>
first <span class="sy1">=</span> ranges<span class="sy4">::</span><span class="me2">adjacent_find</span><span class="br0">(</span>first, last, comp, proj<span class="br0">)</span><span class="sy4">;</span>
<span class="kw1">if</span> <span class="br0">(</span>first <span class="sy1">==</span> last<span class="br0">)</span>
<span class="kw1">return</span> <span class="br0">{</span>first, first<span class="br0">}</span><span class="sy4">;</span>
<span class="kw4">auto</span> i <span class="br0">{</span>first<span class="br0">}</span><span class="sy4">;</span>
<span class="sy2">++</span>first<span class="sy4">;</span>
<span class="kw1">while</span> <span class="br0">(</span><span class="sy2">++</span>first <span class="sy3">!</span><span class="sy1">=</span> last<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>comp, <a href="cpp-utility-functional-invoke.html"><span class="kw1058">std::<span class="me2">invoke</span></span></a><span class="br0">(</span>proj, <span class="sy2">*</span>i<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>proj, <span class="sy2">*</span>first<span class="br0">)</span><span class="br0">)</span><span class="br0">)</span>
<span class="sy2">*++</span>i <span class="sy1">=</span> std<span class="sy4">::</span><span class="me2">move</span><span class="br0">(</span><span class="sy2">*</span>first<span class="br0">)</span><span class="sy4">;</span>
<span class="kw1">return</span> <span class="br0">{</span><span class="sy2">++</span>i, first<span class="br0">}</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">forward_range</span> R, <span class="kw1">class</span> Proj <span class="sy1">=</span> std<span class="sy4">::</span><span class="me2">identity</span>,
std<span class="sy4">::</span><span class="me2">indirect_equivalence_relation</span><span class="sy1">&lt;</span>std<span class="sy4">::</span><span class="me2">projected</span><span class="sy1">&lt;</span>ranges<span class="sy4">::</span><span class="me2">iterator_t</span><span class="sy1">&lt;</span>R<span class="sy1">&gt;</span>, Proj<span class="sy1">&gt;&gt;</span>
C <span class="sy1">=</span> ranges<span class="sy4">::</span><span class="me2">equal_to</span><span class="sy1">&gt;</span>
requires std<span class="sy4">::</span><span class="me2">permutable</span><span class="sy1">&lt;</span>ranges<span class="sy4">::</span><span class="me2">iterator_t</span><span class="sy1">&lt;</span>R<span class="sy1">&gt;&gt;</span>
<span class="kw4">constexpr</span> ranges<span class="sy4">::</span><span class="me2">borrowed_subrange_t</span><span class="sy1">&lt;</span>R<span class="sy1">&gt;</span>
operator<span class="br0">(</span><span class="br0">)</span> <span class="br0">(</span> R<span class="sy3">&amp;&amp;</span> r, C 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> <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>r<span class="br0">)</span>, ranges<span class="sy4">::</span><span class="me2">end</span><span class="br0">(</span>r<span class="br0">)</span>,
std<span class="sy4">::</span><span class="me2">move</span><span class="br0">(</span>comp<span class="br0">)</span>, std<span class="sy4">::</span><span class="me2">move</span><span class="br0">(</span>proj<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> unique_fn unique<span class="br0">{</span><span class="br0">}</span><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">
<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;cmath&gt;</span>
<span class="co2">#include &lt;complex&gt;</span>
<span class="co2">#include &lt;iostream&gt;</span>
<span class="co2">#include &lt;vector&gt;</span>
<span class="kw1">struct</span> id <span class="br0">{</span> <span class="kw4">int</span> i<span class="sy4">;</span> <span class="kw1">explicit</span> id<span class="br0">(</span><span class="kw4">int</span> i<span class="br0">)</span> <span class="sy4">:</span> i<span class="br0">{</span>i<span class="br0">}</span> <span class="br0">{</span><span class="br0">}</span> <span class="br0">}</span><span class="sy4">;</span>
<span class="kw4">void</span> print<span class="br0">(</span>id i, <span class="kw4">const</span> <span class="kw4">auto</span><span class="sy3">&amp;</span> v<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;@&quot;</span> <span class="sy1">&lt;&lt;</span> i.<span class="me1">i</span> <span class="sy1">&lt;&lt;</span> <span class="st0">&quot;: &quot;</span><span class="sy4">;</span>
std<span class="sy4">::</span><span class="me2">ranges</span><span class="sy4">::</span><span class="me2">for_each</span><span class="br0">(</span>v, <span class="br0">[</span><span class="br0">]</span><span class="br0">(</span><span class="kw4">auto</span> <span class="kw4">const</span><span class="sy3">&amp;</span> e<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> e <span class="sy1">&lt;&lt;</span> <span class="st0">&#39; &#39;</span><span class="sy4">;</span> <span class="br0">}</span><span class="br0">)</span><span class="sy4">;</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">&#39;<span class="es1">\n</span>&#39;</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>
<span class="co1">// &#21547;&#25968;&#20010;&#37325;&#22797;&#20803;&#32032;&#30340; vector</span>
<a href="cpp-container-vector.html"><span class="kw1269">std::<span class="me2">vector</span></span></a><span class="sy1">&lt;</span><span class="kw4">int</span><span class="sy1">&gt;</span> v<span class="br0">{</span><span class="nu0">1</span>, <span class="nu0">2</span>, <span class="nu0">1</span>, <span class="nu0">1</span>, <span class="nu0">3</span>, <span class="nu0">3</span>, <span class="nu0">3</span>, <span class="nu0">4</span>, <span class="nu0">5</span>, <span class="nu0">4</span><span class="br0">}</span><span class="sy4">;</span>
print<span class="br0">(</span>id<span class="br0">{</span><span class="nu0">1</span><span class="br0">}</span>, v<span class="br0">)</span><span class="sy4">;</span>
<span class="co1">// &#31227;&#38500;&#36830;&#32493;&#65288;&#30456;&#25509;&#65289;&#30340;&#21103;&#26412;</span>
<span class="kw4">auto</span> ret <span class="sy1">=</span> std<span class="sy4">::</span><span class="me2">ranges</span><span class="sy4">::</span><span class="me2">unique</span><span class="br0">(</span>v<span class="br0">)</span><span class="sy4">;</span>
<span class="co1">// v &#29616;&#22312;&#20445;&#26377; {1 2 1 3 4 5 4 x x x} &#65292;&#20854;&#20013; &#39;x&#39; &#19981;&#30830;&#23450;</span>
v.<span class="me1">erase</span><span class="br0">(</span>ret.<span class="me1">begin</span><span class="br0">(</span><span class="br0">)</span>, ret.<span class="me1">end</span><span class="br0">(</span><span class="br0">)</span><span class="br0">)</span><span class="sy4">;</span>
print<span class="br0">(</span>id<span class="br0">{</span><span class="nu0">2</span><span class="br0">}</span>, v<span class="br0">)</span><span class="sy4">;</span>
<span class="co1">// sort &#21518;&#38543; unique &#65292;&#31227;&#38500;&#25152;&#26377;&#21103;&#26412;</span>
std<span class="sy4">::</span><span class="me2">ranges</span><span class="sy4">::</span><span class="me2">sort</span><span class="br0">(</span>v<span class="br0">)</span><span class="sy4">;</span> <span class="co1">// {1 1 2 3 4 4 5}</span>
print<span class="br0">(</span>id<span class="br0">{</span><span class="nu0">3</span><span class="br0">}</span>, v<span class="br0">)</span><span class="sy4">;</span>
<span class="kw4">auto</span> <span class="br0">[</span>first, last<span class="br0">]</span> <span class="sy1">=</span> std<span class="sy4">::</span><span class="me2">ranges</span><span class="sy4">::</span><span class="me2">unique</span><span class="br0">(</span>v.<span class="me1">begin</span><span class="br0">(</span><span class="br0">)</span>, v.<span class="me1">end</span><span class="br0">(</span><span class="br0">)</span><span class="br0">)</span><span class="sy4">;</span>
<span class="co1">// v &#29616;&#22312;&#20445;&#26377; {1 2 3 4 5 x x} &#65292;&#20854;&#20013; &#39;x&#39; &#19981;&#30830;&#23450;</span>
v.<span class="me1">erase</span><span class="br0">(</span>first, last<span class="br0">)</span><span class="sy4">;</span>
print<span class="br0">(</span>id<span class="br0">{</span><span class="nu0">4</span><span class="br0">}</span>, v<span class="br0">)</span><span class="sy4">;</span>
<span class="co1">// &#20197;&#23450;&#21046;&#27604;&#36739;&#19982;&#25237;&#24433; unique</span>
<a href="cpp-container-vector.html"><span class="kw1269">std::<span class="me2">vector</span></span></a><span class="sy1">&lt;</span><a href="cpp-numeric-complex.html"><span class="kw1472">std::<span class="me2">complex</span></span></a><span class="sy1">&lt;</span><span class="kw4">int</span><span class="sy1">&gt;&gt;</span> vc<span class="br0">{</span> <span class="br0">{</span><span class="nu0">1</span>, <span class="nu0">1</span><span class="br0">}</span>, <span class="br0">{</span><span class="sy2">-</span><span class="nu0">1</span>, <span class="nu0">2</span><span class="br0">}</span>, <span class="br0">{</span><span class="sy2">-</span><span class="nu0">2</span>, <span class="nu0">3</span><span class="br0">}</span>, <span class="br0">{</span><span class="nu0">2</span>, <span class="nu0">4</span><span class="br0">}</span>, <span class="br0">{</span><span class="sy2">-</span><span class="nu0">3</span>, <span class="nu0">5</span><span class="br0">}</span> <span class="br0">}</span><span class="sy4">;</span>
print<span class="br0">(</span>id<span class="br0">{</span><span class="nu0">5</span><span class="br0">}</span>, vc<span class="br0">)</span><span class="sy4">;</span>
<span class="kw4">auto</span> ret2 <span class="sy1">=</span> std<span class="sy4">::</span><span class="me2">ranges</span><span class="sy4">::</span><span class="me2">unique</span><span class="br0">(</span>vc,
<span class="br0">[</span><span class="br0">]</span><span class="br0">(</span><span class="kw4">int</span> x, <span class="kw4">int</span> y<span class="br0">)</span> <span class="br0">{</span> <span class="kw1">return</span> std<span class="sy4">::</span><span class="me2">abs</span><span class="br0">(</span>x<span class="br0">)</span> <span class="sy1">==</span> std<span class="sy4">::</span><span class="me2">abs</span><span class="br0">(</span>y<span class="br0">)</span><span class="sy4">;</span> <span class="br0">}</span>, <span class="co1">// comp</span>
<span class="br0">[</span><span class="br0">]</span><span class="br0">(</span><a href="cpp-numeric-complex.html"><span class="kw1472">std::<span class="me2">complex</span></span></a><span class="sy1">&lt;</span><span class="kw4">int</span><span class="sy1">&gt;</span> z<span class="br0">)</span> <span class="br0">{</span> <span class="kw1">return</span> z.<span class="me1">real</span><span class="br0">(</span><span class="br0">)</span><span class="sy4">;</span> <span class="br0">}</span> <span class="co1">// proj</span>
<span class="br0">)</span><span class="sy4">;</span>
vc.<span class="me1">erase</span><span class="br0">(</span>ret2.<span class="me1">begin</span><span class="br0">(</span><span class="br0">)</span>, ret2.<span class="me1">end</span><span class="br0">(</span><span class="br0">)</span><span class="br0">)</span><span class="sy4">;</span>
print<span class="br0">(</span>id<span class="br0">{</span><span class="nu0">6</span><span class="br0">}</span>, vc<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">@1: 1 2 1 1 3 3 3 4 5 4
@2: 1 2 1 3 4 5 4
@3: 1 1 2 3 4 4 5
@4: 1 2 3 4 5
@5: (1,1) (-1,2) (-2,3) (2,4) (-3,5)
@6: (1,1) (-2,3) (-3,5)</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-unique_copy.html"><span class="t-lines"><span>ranges::unique_copy</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>&#21019;&#24314;&#26576;&#33539;&#22260;&#30340;&#19981;&#21547;&#36830;&#32493;&#37325;&#22797;&#20803;&#32032;&#30340;&#21103;&#26412;<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-adjacent_find.html"><span class="t-lines"><span>ranges::adjacent_find</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>&#26597;&#25214;&#39318;&#23545;&#30456;&#37051;&#30340;&#30456;&#21516;&#65288;&#25110;&#28385;&#36275;&#32473;&#23450;&#35859;&#35789;&#30340;&#65289;&#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-remove.html"><span class="t-lines"><span>ranges::remove</span><span>ranges::remove_if</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></div>
</div>
</td>
<td>&#31227;&#38500;&#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-unique.html"><span class="t-lines"><span>unique</span></span></a></div>
</div>
</td>
<td>&#31227;&#38500;&#33539;&#22260;&#20869;&#30340;&#36830;&#32493;&#37325;&#22797;&#20803;&#32032;<br />
<span class="t-mark">(&#20989;&#25968;&#27169;&#26495;)</span></td>
</tr>
<tr class="t-dsc">
<td>
<div class="t-dsc-member-div">
<div><a href="cpp-container-list-unique.html"><span class="t-lines"><span>unique</span></span></a></div>
</div>
</td>
<td>&#21024;&#38500;&#36830;&#32493;&#30340;&#37325;&#22797;&#20803;&#32032;<br />
<span class="t-mark">(<code>std::list&lt;T,Allocator&gt;</code> &#30340;&#20844;&#24320;&#25104;&#21592;&#20989;&#25968;)</span></td>
</tr>
<tr class="t-dsc">
<td>
<div class="t-dsc-member-div">
<div><a href="cpp-container-forward_list-unique.html"><span class="t-lines"><span>unique</span></span></a></div>
<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx11">(C++11)</span></span></span></div>
</div>
</td>
<td>&#21024;&#38500;&#36830;&#32493;&#30340;&#37325;&#22797;&#20803;&#32032;<br />
<span class="t-mark">(<code>std::forward_list&lt;T,Allocator&gt;</code> &#30340;&#20844;&#24320;&#25104;&#21592;&#20989;&#25968;)</span></td>
</tr>
</table>
</div>
<div class="visualClear"></div>
</div>
</div>
</div>
</body>
</html>