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<h1 id="firstHeading" class="firstHeading"><span style="font-size:0.7em; line-height:130%">std::vector&lt;T,Allocator&gt;::</span>push_back</h1>
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<td rowspan="142">(1)</td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw4">void</span> push_back<span class="br0">(</span> <span class="kw4">const</span> T<span class="sy3">&amp;</span> value <span class="br0">)</span><span class="sy4">;</span></span></div>
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<td><span class="t-mark-rev t-until-cxx20">(C++20 &#21069;)</span></td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw4">constexpr</span> <span class="kw4">void</span> push_back<span class="br0">(</span> <span class="kw4">const</span> T<span class="sy3">&amp;</span> value <span class="br0">)</span><span class="sy4">;</span></span></div>
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<td><span class="t-mark-rev t-since-cxx20">(C++20 &#36215;)</span></td>
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<td rowspan="142">(2)</td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw4">void</span> push_back<span class="br0">(</span> T<span class="sy3">&amp;&amp;</span> value <span class="br0">)</span><span class="sy4">;</span></span></div>
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<td><span class="t-mark-rev t-since-cxx11">(C++11 &#36215;)</span><br />
<span class="t-mark-rev t-until-cxx20">(C++20 &#21069;)</span></td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw4">constexpr</span> <span class="kw4">void</span> push_back<span class="br0">(</span> T<span class="sy3">&amp;&amp;</span> value <span class="br0">)</span><span class="sy4">;</span></span></div>
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<td><span class="t-mark-rev t-since-cxx20">(C++20 &#36215;)</span></td>
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<p>&#21518;&#38468;&#32473;&#23450;&#20803;&#32032; <code>value</code> &#21040;&#23481;&#22120;&#23614;&#12290;</p>
<div class="t-li1"><span class="t-li">1)</span> &#21021;&#22987;&#21270;&#26032;&#20803;&#32032;&#20026; <code>value</code> &#30340;&#21103;&#26412;&#12290;</div>
<div class="t-li1"><span class="t-li">2)</span> &#31227;&#21160; <code>value</code> &#36827;&#26032;&#20803;&#32032;&#12290;</div>
<p>&#33509;&#26032;&#30340; <span class="t-lc"><a href="cpp-container-vector-size.html">size()</a></span> &#22823;&#20110; <span class="t-lc"><a href="cpp-container-vector-capacity.html">capacity()</a></span> &#65292;&#21017;&#25152;&#26377;&#36845;&#20195;&#22120;&#21644;&#24341;&#29992;&#65288;&#21253;&#21547;&#23614;&#21518;&#36845;&#20195;&#22120;&#65289;&#37117;&#34987;&#38750;&#27861;&#21270;&#12290;&#21542;&#21017;&#20165;&#23614;&#21518;&#36845;&#20195;&#22120;&#34987;&#38750;&#27861;&#21270;&#12290;</p>
<h3><span class="mw-headline" id=".E5.8F.82.E6.95.B0">&#21442;&#25968;</span></h3>
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<td>value</td>
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<td>&#35201;&#21518;&#38468;&#30340;&#20803;&#32032;&#20540;</td>
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<td colspan="3">&#31867;&#22411;&#35201;&#27714;</td>
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&#20026;&#20351;&#29992;&#37325;&#36733; (1) &#65292; <code>T</code> &#24517;&#39035;&#28385;&#36275;<a href="cpp-named_req-CopyInsertable.html"><span style="font-style:italic">&#21487;&#22797;&#21046;&#25554;&#20837;</span> <span style="font-family: Georgia, &#39;DejaVu Serif&#39;, serif; font-style:italic">(CopyInsertable)</span></a> &#30340;&#35201;&#27714;&#12290;</td>
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&#20026;&#20351;&#29992;&#37325;&#36733; (2) &#65292; <code>T</code> &#24517;&#39035;&#28385;&#36275;<a href="cpp-named_req-MoveInsertable.html"><span style="font-style:italic">&#21487;&#31227;&#21160;&#25554;&#20837;</span> <span style="font-family: Georgia, &#39;DejaVu Serif&#39;, serif; font-style:italic">(MoveInsertable)</span></a> &#30340;&#35201;&#27714;&#12290;</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>
<h3><span class="mw-headline" id=".E5.A4.8D.E6.9D.82.E5.BA.A6">&#22797;&#26434;&#24230;</span></h3>
<p>&#22343;&#25674;&#24120;&#25968;&#12290;</p>
<h3><span class="mw-headline" id=".E5.BC.82.E5.B8.B8">&#24322;&#24120;</span></h3>
<p>&#33509;&#25243;&#20986;&#24322;&#24120;&#65288;&#21487;&#33021;&#22240;&#20026; <code>Allocator::allocate()</code> &#25110;&#20803;&#32032;&#22797;&#21046;/&#31227;&#21160;&#26500;&#36896;&#20989;&#25968;/&#36171;&#20540;&#65289;&#65292;&#21017;&#27492;&#20989;&#25968;&#26080;&#25928;&#26524;&#65288;&#24378;&#24322;&#24120;&#20445;&#35777;&#65289;&#12290;</p>
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<p>&#33509; <code>T</code> &#30340;&#31227;&#21160;&#26500;&#36896;&#20989;&#25968;&#19981;&#26159; <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw1">noexcept</span></span></span> &#19988; T &#19981;<a href="cpp-named_req-CopyInsertable.html"><span style="font-style:italic">&#21487;&#22797;&#21046;&#25554;&#20837;</span> <span style="font-family: Georgia, &#39;DejaVu Serif&#39;, serif; font-style:italic">(CopyInsertable)</span></a> &#21040; <code>*this</code> &#65292;&#21017; vector &#23558;&#20351;&#29992;&#20250;&#25243;&#20986;&#30340;&#31227;&#21160;&#26500;&#36896;&#20989;&#25968;&#12290;&#33509;&#23427;&#25243;&#20986;&#65292;&#21017;&#25243;&#24323;&#20445;&#35777;&#19988;&#25928;&#26524;&#26410;&#25351;&#23450;&#12290;</p>
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<td><span class="t-mark-rev t-since-cxx11">(C++11 &#36215;)</span></td>
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<h3><span class="mw-headline" id=".E6.B3.A8.E8.A7.A3">&#27880;&#35299;</span></h3>
<p>&#19968;&#20123;&#23454;&#29616;&#22312; <code>push_back</code> &#23548;&#33268;&#20250;&#36229;&#20986; <span class="t-lc"><a href="cpp-container-vector-max_size.html">max_size</a></span> &#30340;&#37325;&#20998;&#37197;&#26102;&#20134;&#25243;&#20986; <span class="t-lc"><a href="cpp-error-length_error.html">std::length_error</a></span> &#65292;&#30001;&#20110;&#36825;&#20250;&#38544;&#24335;&#35843;&#29992; <span class="t-lc">reserve(size()+1)</span> &#30340;&#31561;&#20215;&#32773;&#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;vector&gt;</span>
<span class="co2">#include &lt;iostream&gt;</span>
<span class="co2">#include &lt;iomanip&gt;</span>
<span class="kw4">int</span> main<span class="br0">(</span><span class="br0">)</span>
<span class="br0">{</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-string-basic_string.html"><span class="kw1230">std::<span class="me2">string</span></span></a><span class="sy1">&gt;</span> letters<span class="sy4">;</span>
letters.<span class="me1">push_back</span><span class="br0">(</span><span class="st0">&quot;abc&quot;</span><span class="br0">)</span><span class="sy4">;</span>
<a href="cpp-string-basic_string.html"><span class="kw1230">std::<span class="me2">string</span></span></a> s <span class="sy1">=</span> <span class="st0">&quot;def&quot;</span><span class="sy4">;</span>
letters.<span class="me1">push_back</span><span class="br0">(</span>std<span class="sy4">::</span><span class="me2">move</span><span class="br0">(</span>s<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;vector holds: &quot;</span><span class="sy4">;</span>
<span class="kw1">for</span> <span class="br0">(</span><span class="kw4">auto</span><span class="sy3">&amp;&amp;</span> i <span class="sy4">:</span> letters<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> <a href="cpp-io-manip-quoted.html"><span class="kw1802">std::<span class="me2">quoted</span></span></a><span class="br0">(</span>i<span class="br0">)</span> <span class="sy1">&lt;&lt;</span> <span class="st0">&#39; &#39;</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;<span class="es1">\n</span>Moved-from string holds &quot;</span> <span class="sy1">&lt;&lt;</span> <a href="cpp-io-manip-quoted.html"><span class="kw1802">std::<span class="me2">quoted</span></span></a><span class="br0">(</span>s<span class="br0">)</span> <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></pre></div>
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<p>&#36755;&#20986;&#65306;</p>
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<pre class="de1">vector holds: &quot;abc&quot; &quot;def&quot;
Moved-from string holds &quot;&quot;</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><a href="cpp-container-vector-emplace_back.html"><span class="t-lines"><span>emplace_back</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>&#22312;&#23481;&#22120;&#26411;&#23614;&#23601;&#22320;&#26500;&#36896;&#20803;&#32032;<br />
<span class="t-mark">(&#20844;&#24320;&#25104;&#21592;&#20989;&#25968;)</span></td>
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<div><a href="cpp-container-vector-pop_back.html"><span class="t-lines"><span>pop_back</span></span></a></div>
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<td>&#31227;&#38500;&#26411;&#20803;&#32032;<br />
<span class="t-mark">(&#20844;&#24320;&#25104;&#21592;&#20989;&#25968;)</span></td>
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