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<h1 id="firstHeading" class="firstHeading"><span style="font-size:0.7em; line-height:130%">std::unordered_multimap&lt;Key,T,Hash,KeyEqual,Allocator&gt;::</span>merge</h1>
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<div id="contentSub"><span class="subpages">&lt; <a href="cpp.html">cpp</a>&lrm; | <a href="cpp-container.html">container</a>&lrm; | <a href="cpp-container-unordered_multimap.html">unordered multimap</a></span></div>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1">&lt;</span><span class="kw1">class</span> H2, <span class="kw1">class</span> P2<span class="sy1">&gt;</span><br />
<span class="kw4">void</span> merge<span class="br0">(</span> <a href="cpp-container-unordered_map.html"><span class="kw1293">std::<span class="me2">unordered_map</span></span></a><span class="sy1">&lt;</span>Key, T, H2, P2, Allocator<span class="sy1">&gt;</span><span class="sy3">&amp;</span> source <span class="br0">)</span><span class="sy4">;</span></span></div>
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<td>(1)</td>
<td><span class="t-mark-rev t-since-cxx17">(C++17 &#36215;)</span></td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1">&lt;</span><span class="kw1">class</span> H2, <span class="kw1">class</span> P2<span class="sy1">&gt;</span><br />
<span class="kw4">void</span> merge<span class="br0">(</span> <a href="cpp-container-unordered_map.html"><span class="kw1293">std::<span class="me2">unordered_map</span></span></a><span class="sy1">&lt;</span>Key, T, H2, P2, Allocator<span class="sy1">&gt;</span><span class="sy3">&amp;&amp;</span> source <span class="br0">)</span><span class="sy4">;</span></span></div>
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<td>(2)</td>
<td><span class="t-mark-rev t-since-cxx17">(C++17 &#36215;)</span></td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1">&lt;</span><span class="kw1">class</span> H2, <span class="kw1">class</span> P2<span class="sy1">&gt;</span><br />
<span class="kw4">void</span> merge<span class="br0">(</span> <a href="cpp-container-unordered_multimap.html"><span class="kw1295">std::<span class="me2">unordered_multimap</span></span></a><span class="sy1">&lt;</span>Key, T, H2, P2, Allocator<span class="sy1">&gt;</span><span class="sy3">&amp;</span> source <span class="br0">)</span><span class="sy4">;</span></span></div>
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<td>(3)</td>
<td><span class="t-mark-rev t-since-cxx17">(C++17 &#36215;)</span></td>
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<tr class="t-dcl t-since-cxx17">
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<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1">&lt;</span><span class="kw1">class</span> H2, <span class="kw1">class</span> P2<span class="sy1">&gt;</span><br />
<span class="kw4">void</span> merge<span class="br0">(</span> <a href="cpp-container-unordered_multimap.html"><span class="kw1295">std::<span class="me2">unordered_multimap</span></span></a><span class="sy1">&lt;</span>Key, T, H2, P2, Allocator<span class="sy1">&gt;</span><span class="sy3">&amp;&amp;</span> source <span class="br0">)</span><span class="sy4">;</span></span></div>
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<td>(4)</td>
<td><span class="t-mark-rev t-since-cxx17">(C++17 &#36215;)</span></td>
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<p>&#35797;&#22270;&#25552;&#21462;&#65288;&ldquo;&#25509;&#21512;&rdquo;&#65289; <code>source</code> &#20013;&#27599;&#20010;&#20803;&#32032;&#65292;&#24182;&#29992; <code>*this</code> &#30340;&#25955;&#21015;&#20989;&#25968;&#19982;&#38190;&#30456;&#31561;&#35859;&#35789;&#25554;&#20837;&#21040; <code>*this</code> &#12290;</p>
<p>&#19981;&#22797;&#21046;&#25110;&#31227;&#21160;&#20803;&#32032;&#65292;&#21482;&#20250;&#37325;&#25351;&#21521;&#23481;&#22120;&#32467;&#28857;&#30340;&#20869;&#37096;&#25351;&#38024;&#12290;&#25351;&#21521;&#34987;&#36716;&#31227;&#20803;&#32032;&#30340;&#25152;&#26377;&#25351;&#38024;&#21644;&#24341;&#29992;&#20445;&#25345;&#21512;&#27861;&#65292;&#20294;&#29616;&#22312;&#25351;&#20195;&#21040; <code>*this</code> &#20013;&#32780;&#38750;&#21040; <code>source</code> &#20013;&#12290;&#25351;&#20195;&#34987;&#36716;&#31227;&#20803;&#32032;&#30340;&#36845;&#20195;&#22120;&#21644;&#25152;&#26377;&#25351;&#20195;&#21040; <code>*this</code> &#30340;&#36845;&#20195;&#22120;&#34987;&#38750;&#27861;&#21270;&#12290;</p>
<p>&#33509; <span class="t-c"><span class="mw-geshi cpp source-cpp">get_allocator<span class="br0">(</span><span class="br0">)</span> <span class="sy3">!</span><span class="sy1">=</span> source.<span class="me1">get_allocator</span><span class="br0">(</span><span class="br0">)</span></span></span> &#21017;&#34892;&#20026;&#26410;&#23450;&#20041;&#12290;</p>
<h3><span class="mw-headline" id=".E5.8F.82.E6.95.B0">&#21442;&#25968;</span></h3>
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<td>source</td>
<td>-</td>
<td>&#20256;&#36882;&#32467;&#28857;&#26469;&#28304;&#30340;&#20860;&#23481;&#23481;&#22120;</td>
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<h3><span class="mw-headline" id=".E8.BF.94.E5.9B.9E.E5.80.BC">&#36820;&#22238;&#20540;</span></h3>
<p>&#65288;&#26080;&#65289;</p>
<p><br /></p>
<h3><span class="mw-headline" id=".E5.A4.8D.E6.9D.82.E5.BA.A6">&#22797;&#26434;&#24230;</span></h3>
<p>&#24179;&#22343;&#24773;&#20917; O(N) &#65292;&#26368;&#22351;&#24773;&#20917; O(N*size()+N) &#65292;&#20854;&#20013; N &#20026; <code>source.size()</code> &#12290;</p>
<h3><span class="mw-headline" id=".E7.A4.BA.E4.BE.8B">&#31034;&#20363;</span></h3>
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<pre class="de1"><span class="co2">#include &lt;iostream&gt;</span>
<span class="co2">#include &lt;string&gt;</span>
<span class="co2">#include &lt;utility&gt;</span>
<span class="co2">#include &lt;unordered_map&gt;</span>
<span class="co1">// &#25171;&#21360;&#20986; std::pair</span>
<span class="kw1">template</span> <span class="sy1">&lt;</span><span class="kw1">class</span> Os, <span class="kw1">class</span> U, <span class="kw1">class</span> V<span class="sy1">&gt;</span>
Os<span class="sy3">&amp;</span> operator<span class="sy1">&lt;&lt;</span><span class="br0">(</span>Os<span class="sy3">&amp;</span> os, <span class="kw4">const</span> <a href="cpp-utility-pair.html"><span class="kw1096">std::<span class="me2">pair</span></span></a><span class="sy1">&lt;</span>U,V<span class="sy1">&gt;</span><span class="sy3">&amp;</span> p<span class="br0">)</span> <span class="br0">{</span>
<span class="kw1">return</span> os <span class="sy1">&lt;&lt;</span> <span class="st0">&#39;{&#39;</span> <span class="sy1">&lt;&lt;</span> p.<span class="me1">first</span> <span class="sy1">&lt;&lt;</span> <span class="st0">&quot;, &quot;</span> <span class="sy1">&lt;&lt;</span> p.<span class="me1">second</span> <span class="sy1">&lt;&lt;</span> <span class="st0">&#39;}&#39;</span><span class="sy4">;</span>
<span class="br0">}</span>
<span class="co1">// &#25171;&#21360;&#20986;&#20851;&#32852;&#23481;&#22120;</span>
<span class="kw1">template</span> <span class="sy1">&lt;</span><span class="kw1">class</span> Os, <span class="kw1">class</span> K, <span class="kw1">class</span> V<span class="sy1">&gt;</span>
Os<span class="sy3">&amp;</span> operator<span class="sy1">&lt;&lt;</span><span class="br0">(</span>Os<span class="sy3">&amp;</span> os, <span class="kw4">const</span> <a href="cpp-container-unordered_multimap.html"><span class="kw1295">std::<span class="me2">unordered_multimap</span></span></a><span class="sy1">&lt;</span>K, V<span class="sy1">&gt;</span><span class="sy3">&amp;</span> v<span class="br0">)</span> <span class="br0">{</span>
os <span class="sy1">&lt;&lt;</span> <span class="st0">&#39;[&#39;</span> <span class="sy1">&lt;&lt;</span> v.<span class="me1">size</span><span class="br0">(</span><span class="br0">)</span> <span class="sy1">&lt;&lt;</span> <span class="st0">&quot;] { &quot;</span><span class="sy4">;</span>
<span class="kw4">bool</span> o<span class="br0">{</span><span class="br0">}</span><span class="sy4">;</span>
<span class="kw1">for</span> <span class="br0">(</span><span class="kw4">const</span> <span class="kw4">auto</span><span class="sy3">&amp;</span> e <span class="sy4">:</span> v<span class="br0">)</span>
os <span class="sy1">&lt;&lt;</span> <span class="br0">(</span>o <span class="sy4">?</span> <span class="st0">&quot;, &quot;</span> <span class="sy4">:</span> <span class="br0">(</span>o <span class="sy1">=</span> <span class="nu0">1</span>, <span class="st0">&quot;&quot;</span><span class="br0">)</span><span class="br0">)</span> <span class="sy1">&lt;&lt;</span> e<span class="sy4">;</span>
<span class="kw1">return</span> os <span class="sy1">&lt;&lt;</span> <span class="st0">&quot; }<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>
<a href="cpp-container-unordered_multimap.html"><span class="kw1295">std::<span class="me2">unordered_multimap</span></span></a><span class="sy1">&lt;</span><a href="cpp-string-basic_string.html"><span class="kw1230">std::<span class="me2">string</span></span></a>, <span class="kw4">int</span><span class="sy1">&gt;</span>
p<span class="br0">{</span> <span class="br0">{</span><span class="st0">&quot;C&quot;</span>, <span class="nu0">3</span><span class="br0">}</span>, <span class="br0">{</span><span class="st0">&quot;B&quot;</span>, <span class="nu0">2</span><span class="br0">}</span>, <span class="br0">{</span><span class="st0">&quot;A&quot;</span>, <span class="nu0">1</span><span class="br0">}</span>, <span class="br0">{</span><span class="st0">&quot;A&quot;</span>, <span class="nu0">0</span><span class="br0">}</span> <span class="br0">}</span>,
q<span class="br0">{</span> <span class="br0">{</span><span class="st0">&quot;E&quot;</span>, <span class="nu0">6</span><span class="br0">}</span>, <span class="br0">{</span><span class="st0">&quot;E&quot;</span>, <span class="nu0">7</span><span class="br0">}</span>, <span class="br0">{</span><span class="st0">&quot;D&quot;</span>, <span class="nu0">5</span><span class="br0">}</span>, <span class="br0">{</span><span class="st0">&quot;A&quot;</span>, <span class="nu0">4</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">&quot;p: &quot;</span> <span class="sy1">&lt;&lt;</span> p <span class="sy1">&lt;&lt;</span> <span class="st0">&quot;q: &quot;</span> <span class="sy1">&lt;&lt;</span> q<span class="sy4">;</span>
p.<span class="me1">merge</span><span class="br0">(</span>q<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">&quot;p.merge(q);<span class="es1">\n</span>&quot;</span> <span class="sy1">&lt;&lt;</span> <span class="st0">&quot;p: &quot;</span> <span class="sy1">&lt;&lt;</span> p <span class="sy1">&lt;&lt;</span> <span class="st0">&quot;q: &quot;</span> <span class="sy1">&lt;&lt;</span> q<span class="sy4">;</span>
<span class="br0">}</span></pre></div>
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<p>&#21487;&#33021;&#30340;&#36755;&#20986;&#65306;</p>
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<pre class="de1">p: [4] { {A, 1}, {A, 0}, {B, 2}, {C, 3} }
q: [4] { {A, 4}, {D, 5}, {E, 6}, {E, 7} }
p.merge(q);
p: [8] { {E, 6}, {E, 7}, {C, 3}, {A, 1}, {A, 0}, {A, 4}, {D, 5}, {B, 2} }
q: [0] { }</pre></div>
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<h3><span class="mw-headline" id=".E5.8F.82.E9.98.85">&#21442;&#38405;</span></h3>
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<div class="t-dsc-member-div">
<div><a href="cpp-container-unordered_multimap-extract.html"><span class="t-lines"><span>extract</span></span></a></div>
<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx17">(C++17)</span></span></span></div>
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<td>&#20174;&#21478;&#19968;&#23481;&#22120;&#37322;&#20986;&#32467;&#28857;<br />
<span class="t-mark">(&#20844;&#24320;&#25104;&#21592;&#20989;&#25968;)</span></td>
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<div class="t-dsc-member-div">
<div><a href="cpp-container-unordered_multimap-insert.html"><span class="t-lines"><span>insert</span></span></a></div>
<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx11">(C++11)</span></span></span></div>
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<td>&#25554;&#20837;&#20803;&#32032;<span class="t-rev-inl t-since-cxx17"><span>&#25110;&#32467;&#28857;</span> <span><span class="t-mark-rev t-since-cxx17">(C++17 &#36215;)</span></span></span><br />
<span class="t-mark">(&#20844;&#24320;&#25104;&#21592;&#20989;&#25968;)</span></td>
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