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<title>std::unique_ptr&lt;T,Deleter&gt;::operator[]</title>
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<h1 id="firstHeading" class="firstHeading"><span style="font-size:0.7em; line-height:130%">std::unique_ptr&lt;T,Deleter&gt;::</span>operator[]</h1>
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<div id="contentSub"><span class="subpages">&lt; <a href="cpp.html">cpp</a>&lrm; | <a href="cpp-memory.html">memory</a>&lrm; | <a href="cpp-memory-unique_ptr.html">unique ptr</a></span></div>
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<div><span class="mw-geshi cpp source-cpp">T<span class="sy3">&amp;</span> operator<span class="br0">[</span><span class="br0">]</span><span class="br0">(</span> <a href="cpp-types-size_t.html"><span class="kw100">std::<span class="me2">size_t</span></span></a> i <span class="br0">)</span> <span class="kw4">const</span><span class="sy4">;</span></span></div>
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<td><span class="t-mark-rev t-since-cxx11">(C++11 &#36215;)</span></td>
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<p><code>operator[]</code> &#25552;&#20379;&#23545; <code>unique_ptr</code> &#25152;&#31649;&#29702;&#30340;&#25968;&#32452;&#20803;&#32032;&#30340;&#35775;&#38382;&#12290;</p>
<p>&#21442;&#25968; <code>i</code> &#24517;&#39035;&#23567;&#20110;&#25968;&#32452;&#20013;&#30340;&#20803;&#32032;&#25968;&#65307;&#21542;&#21017;&#34892;&#20026;&#26410;&#23450;&#20041;&#12290;</p>
<p>&#20165;&#20026;&#23545;&#20110;&#25968;&#32452;&#31867;&#22411;&#30340;&#29305;&#21270;&#25552;&#20379;&#27492;&#25104;&#21592;&#20989;&#25968;&#12290;</p>
<h3><span class="mw-headline" id=".E5.8F.82.E6.95.B0">&#21442;&#25968;</span></h3>
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<td>i</td>
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<td>&#35201;&#36820;&#22238;&#30340;&#20803;&#32032;&#30340;&#32034;&#24341;</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>&#36820;&#22238;&#22312;&#32034;&#24341; <code>i</code> &#30340;&#20803;&#32032;&#65292;&#21363; <span class="t-c"><span class="mw-geshi cpp source-cpp">get<span class="br0">(</span><span class="br0">)</span><span class="br0">[</span>i<span class="br0">]</span></span></span> &#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;memory&gt;</span>
<span class="kw4">int</span> main<span class="br0">(</span><span class="br0">)</span>
<span class="br0">{</span>
<span class="kw4">const</span> <span class="kw4">int</span> size <span class="sy1">=</span> <span class="nu0">10</span><span class="sy4">;</span>
<a href="cpp-memory-unique_ptr.html"><span class="kw733">std::<span class="me2">unique_ptr</span></span></a><span class="sy1">&lt;</span><span class="kw4">int</span><span class="br0">[</span><span class="br0">]</span><span class="sy1">&gt;</span> fact<span class="br0">(</span>new <span class="kw4">int</span><span class="br0">[</span>size<span class="br0">]</span><span class="br0">)</span><span class="sy4">;</span>
<span class="kw1">for</span> <span class="br0">(</span><span class="kw4">int</span> i <span class="sy1">=</span> <span class="nu0">0</span><span class="sy4">;</span> i <span class="sy1">&lt;</span> size<span class="sy4">;</span> <span class="sy2">++</span>i<span class="br0">)</span> <span class="br0">{</span>
fact<span class="br0">[</span>i<span class="br0">]</span> <span class="sy1">=</span> <span class="br0">(</span>i <span class="sy1">==</span> <span class="nu0">0</span><span class="br0">)</span> <span class="sy4">?</span> <span class="nu0">1</span> <span class="sy4">:</span> i <span class="sy2">*</span> fact<span class="br0">[</span>i<span class="sy2">-</span><span class="nu0">1</span><span class="br0">]</span><span class="sy4">;</span>
<span class="br0">}</span>
<span class="kw1">for</span> <span class="br0">(</span><span class="kw4">int</span> i <span class="sy1">=</span> <span class="nu0">0</span><span class="sy4">;</span> i <span class="sy1">&lt;</span> size<span class="sy4">;</span> <span class="sy2">++</span>i<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> i <span class="sy1">&lt;&lt;</span> <span class="st0">&quot;: &quot;</span> <span class="sy1">&lt;&lt;</span> fact<span class="br0">[</span>i<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>
<span class="br0">}</span></pre></div>
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<p>&#36755;&#20986;&#65306;</p>
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<pre class="de1">0: 1
1: 1
2: 2
3: 6
4: 24
5: 120
6: 720
7: 5040
8: 40320
9: 362880</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-memory-unique_ptr-get.html"><span class="t-lines"><span>get</span></span></a></div>
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<td>&#36820;&#22238;&#25351;&#21521;&#34987;&#31649;&#29702;&#23545;&#35937;&#30340;&#25351;&#38024;<br />
<span class="t-mark">(&#20844;&#24320;&#25104;&#21592;&#20989;&#25968;)</span></td>
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