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<h1 id="firstHeading" class="firstHeading"><span style="font-size:0.7em; line-height:130%">std::</span>move_backward</h1>
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<div id="contentSub"><span class="subpages">&lt; <a href="cpp.html">cpp</a>&lrm; | <a href="cpp-algorithm.html">algorithm</a></span></div>
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<div>&#23450;&#20041;&#20110;&#22836;&#25991;&#20214; <code><a href="cpp-header-algorithm.html">&lt;algorithm&gt;</a></code></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> BidirIt1, <span class="kw1">class</span> BidirIt2 <span class="sy1">&gt;</span><br />
BidirIt2 move_backward<span class="br0">(</span> BidirIt1 first, BidirIt1 last, BidirIt2 d_last <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="kw1">template</span><span class="sy1">&lt;</span> <span class="kw1">class</span> BidirIt1, <span class="kw1">class</span> BidirIt2 <span class="sy1">&gt;</span><br />
<span class="kw4">constexpr</span> BidirIt2 move_backward<span class="br0">(</span> BidirIt1 first, BidirIt1 last, BidirIt2 d_last <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>&#31227;&#21160;&#26469;&#33258;&#33539;&#22260; <code>[first, last)</code> &#30340;&#20803;&#32032;&#21040;&#32456;&#20110; <code>d_last</code> &#30340;&#21478;&#19968;&#33539;&#22260;&#12290;&#20197;&#36870;&#24207;&#31227;&#21160;&#20803;&#32032;&#65288;&#39318;&#20808;&#22797;&#21046;&#26411;&#20803;&#32032;&#65289;&#65292;&#20294;&#20445;&#25345;&#20854;&#30456;&#23545;&#39034;&#24207;&#12290;</p>
<p>&#33509; <code>d_last</code> &#22312; <code>(first, last]</code> &#20869;&#21017;&#34892;&#20026;&#26410;&#23450;&#20041;&#12290;&#35813;&#24773;&#20917;&#19979;&#24517;&#39035;&#29992; <a href="cpp-algorithm-move.html"><tt>std::move</tt></a> &#20195;&#26367; <code>std::move_backward</code> &#12290;</p>
<h3><span class="mw-headline" id=".E5.8F.82.E6.95.B0">&#21442;&#25968;</span></h3>
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<td>first, last</td>
<td>-</td>
<td>&#35201;&#31227;&#21160;&#30340;&#20803;&#32032;&#33539;&#22260;</td>
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<td>d_last</td>
<td>-</td>
<td>&#30446;&#26631;&#33539;&#22260;&#32467;&#23614;</td>
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<td colspan="3">&#31867;&#22411;&#35201;&#27714;</td>
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<code>BidirIt1, BidirIt2</code> &#24517;&#39035;&#28385;&#36275;<a href="cpp-named_req-BidirectionalIterator.html"><span style="font-style:italic">&#32769;&#24335;&#21452;&#21521;&#36845;&#20195;&#22120;</span> <span style="font-family: Georgia, &#39;DejaVu Serif&#39;, serif; font-style:italic">(LegacyBidirectionalIterator)</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>&#30446;&#26631;&#33539;&#22260;&#20013;&#30340;&#36845;&#20195;&#22120;&#65292;&#25351;&#21521;&#26368;&#21518;&#31227;&#21160;&#30340;&#20803;&#32032;&#12290;</p>
<h3><span class="mw-headline" id=".E5.A4.8D.E6.9D.82.E5.BA.A6">&#22797;&#26434;&#24230;</span></h3>
<p>&#20934;&#30830;&#31227;&#21160;&#36171;&#20540; <code>last - first</code> &#27425;&#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>
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<pre class="de1"><span class="kw1">template</span><span class="sy1">&lt;</span> <span class="kw1">class</span> BidirIt1, <span class="kw1">class</span> BidirIt2 <span class="sy1">&gt;</span>
BidirIt2 move_backward<span class="br0">(</span>BidirIt1 first,
BidirIt1 last,
BidirIt2 d_last<span class="br0">)</span>
<span class="br0">{</span>
<span class="kw1">while</span> <span class="br0">(</span>first <span class="sy3">!</span><span class="sy1">=</span> last<span class="br0">)</span> <span class="br0">{</span>
<span class="sy2">*</span><span class="br0">(</span><span class="sy2">--</span>d_last<span class="br0">)</span> <span class="sy1">=</span> std<span class="sy4">::</span><span class="me2">move</span><span class="br0">(</span><span class="sy2">*</span><span class="br0">(</span><span class="sy2">--</span>last<span class="br0">)</span><span class="br0">)</span><span class="sy4">;</span>
<span class="br0">}</span>
<span class="kw1">return</span> d_last<span class="sy4">;</span>
<span class="br0">}</span></pre></div>
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<h3><span class="mw-headline" id=".E6.B3.A8.E8.A7.A3">&#27880;&#35299;</span></h3>
<p>&#31227;&#21160;&#37325;&#21472;&#30340;&#33539;&#22260;&#26102;&#65292; <span class="t-lc">std::move</span> &#36866;&#21512;&#21521;&#24038;&#31227;&#21160;&#65288;&#30446;&#26631;&#33539;&#22260;&#30340;&#36215;&#22987;&#22312;&#28304;&#33539;&#22260;&#22806;&#65289;&#26102;&#65292;&#32780; <code>std::move_backward</code> &#36866;&#21512;&#21521;&#21491;&#31227;&#21160;&#65288;&#30446;&#26631;&#33539;&#22260;&#30340;&#32467;&#23614;&#22312;&#28304;&#33539;&#22260;&#22806;&#65289;&#26102;&#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;algorithm&gt;</span>
<span class="co2">#include &lt;vector&gt;</span>
<span class="co2">#include &lt;string&gt;</span>
<span class="co2">#include &lt;iostream&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> src<span class="br0">{</span><span class="st0">&quot;foo&quot;</span>, <span class="st0">&quot;bar&quot;</span>, <span class="st0">&quot;baz&quot;</span><span class="br0">}</span><span class="sy4">;</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> dest<span class="br0">(</span>src.<span class="me1">size</span><span class="br0">(</span><span class="br0">)</span><span class="br0">)</span><span class="sy4">;</span>
<a href="cpp-io-cout.html"><span class="kw1757">std::<span class="me2">cout</span></span></a> <span class="sy1">&lt;&lt;</span> <span class="st0">&quot;src: &quot;</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>s <span class="sy4">:</span> src<span class="br0">)</span>
<span class="br0">{</span>
<a href="cpp-io-cout.html"><span class="kw1757">std::<span class="me2">cout</span></span></a> <span class="sy1">&lt;&lt;</span> s <span class="sy1">&lt;&lt;</span> <span class="st0">&#39; &#39;</span><span class="sy4">;</span>
<span class="br0">}</span>
<a href="cpp-io-cout.html"><span class="kw1757">std::<span class="me2">cout</span></span></a> <span class="sy1">&lt;&lt;</span> <span class="st0">&quot;<span class="es1">\n</span>dest: &quot;</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>s <span class="sy4">:</span> dest<span class="br0">)</span>
<span class="br0">{</span>
<a href="cpp-io-cout.html"><span class="kw1757">std::<span class="me2">cout</span></span></a> <span class="sy1">&lt;&lt;</span> s <span class="sy1">&lt;&lt;</span> <span class="st0">&#39; &#39;</span><span class="sy4">;</span>
<span class="br0">}</span>
<a href="cpp-io-cout.html"><span class="kw1757">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>
std<span class="sy4">::</span><span class="me2">move_backward</span><span class="br0">(</span>src.<span class="me1">begin</span><span class="br0">(</span><span class="br0">)</span>, src.<span class="me1">end</span><span class="br0">(</span><span class="br0">)</span>, dest.<span class="me1">end</span><span class="br0">(</span><span class="br0">)</span><span class="br0">)</span><span class="sy4">;</span>
<a href="cpp-io-cout.html"><span class="kw1757">std::<span class="me2">cout</span></span></a> <span class="sy1">&lt;&lt;</span> <span class="st0">&quot;src: &quot;</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>s <span class="sy4">:</span> src<span class="br0">)</span>
<span class="br0">{</span>
<a href="cpp-io-cout.html"><span class="kw1757">std::<span class="me2">cout</span></span></a> <span class="sy1">&lt;&lt;</span> s <span class="sy1">&lt;&lt;</span> <span class="st0">&#39; &#39;</span><span class="sy4">;</span>
<span class="br0">}</span>
<a href="cpp-io-cout.html"><span class="kw1757">std::<span class="me2">cout</span></span></a> <span class="sy1">&lt;&lt;</span> <span class="st0">&quot;<span class="es1">\n</span>dest: &quot;</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>s <span class="sy4">:</span> dest<span class="br0">)</span>
<span class="br0">{</span>
<a href="cpp-io-cout.html"><span class="kw1757">std::<span class="me2">cout</span></span></a> <span class="sy1">&lt;&lt;</span> s <span class="sy1">&lt;&lt;</span> <span class="st0">&#39; &#39;</span><span class="sy4">;</span>
<span class="br0">}</span>
<a href="cpp-io-cout.html"><span class="kw1757">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></pre></div>
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<p>&#36755;&#20986;&#65306;</p>
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<pre class="de1">src: foo bar baz
dest:
src:
dest: foo bar baz</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-algorithm-move.html"><span class="t-lines"><span>move</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>&#23558;&#26576;&#19968;&#33539;&#22260;&#30340;&#20803;&#32032;&#31227;&#21160;&#21040;&#19968;&#20010;&#26032;&#30340;&#20301;&#32622;<br />
<span class="t-mark">(&#20989;&#25968;&#27169;&#26495;)</span></td>
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<div><a href="cpp-algorithm-ranges-move_backward.html"><span class="t-lines"><span>ranges::move_backword</span></span></a></div>
<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx20">(C++20)</span></span></span></div>
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<td>&#25353;&#20174;&#21518;&#24448;&#21069;&#30340;&#39034;&#24207;&#31227;&#21160;&#26576;&#19968;&#33539;&#22260;&#30340;&#20803;&#32032;&#21040;&#26032;&#30340;&#20301;&#32622;<br />
<span class="t-mark">(niebloid)</span></td>
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