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<h1 id="firstHeading" class="firstHeading"><span style="font-size:0.7em; line-height:130%">std::bitset&lt;N&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-utility.html">utility</a>&lrm; | <a href="cpp-utility-bitset.html">bitset</a></span></div>
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<td rowspan="142">(1)</td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw4">bool</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> pos <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-until-cxx11">(C++11 &#21069;)</span></td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw4">constexpr</span> <span class="kw4">bool</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> pos <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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<div><span class="mw-geshi cpp source-cpp">reference 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> pos <span class="br0">)</span><span class="sy4">;</span></span></div>
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<td>(2)</td>
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<p>&#35775;&#38382;&#20301;&#20110;&#20301;&#32622; <code>pos</code> &#30340;&#20301;&#12290;&#39318;&#29256;&#26412;&#36820;&#22238;&#20301;&#30340;&#20540;&#65292;&#31532;&#20108;&#29256;&#26412;&#36820;&#22238;&#20801;&#35768;&#20462;&#25913;&#20301;&#30340;&#20540;&#30340; <span class="t-lc"><a href="cpp-utility-bitset-reference.html">std::bitset::reference</a></span> &#23545;&#35937;&#12290;</p>
<p>&#19981;&#21516;&#20110; <span class="t-lc"><a href="cpp-utility-bitset-test.html">test()</a></span> &#65292;&#23427;&#19981;&#25243;&#24322;&#24120;&#65306;&#33509; <code>pos</code> &#22312;&#36793;&#30028;&#22806;&#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>pos</td>
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<td>&#35201;&#36820;&#22238;&#30340;&#20301;&#30340;&#20301;&#32622;</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>1) &#35831;&#27714;&#20301;&#30340;&#20540;</p>
<p>2) <span class="t-lc"><a href="cpp-utility-bitset-reference.html">std::bitset::reference</a></span> &#31867;&#22411;&#23545;&#35937;&#65292;&#20801;&#35768;&#20889;&#20837;&#35831;&#27714;&#20301;&#12290;</p>
<h3><span class="mw-headline" id=".E5.BC.82.E5.B8.B8">&#24322;&#24120;</span></h3>
<p>&#65288;&#26080;&#65289;</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;bitset&gt;</span>
<span class="kw4">int</span> main<span class="br0">(</span><span class="br0">)</span>
<span class="br0">{</span>
<a href="cpp-utility-bitset.html"><span class="kw1027">std::<span class="me2">bitset</span></span></a><span class="sy1">&lt;</span><span class="nu0">8</span><span class="sy1">&gt;</span> b1<span class="br0">(</span><span class="nu0">42</span><span class="br0">)</span><span class="sy4">;</span>
<span class="kw1">for</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="sy1">=</span> <span class="nu0">0</span><span class="sy4">;</span> i <span class="sy1">&lt;</span> b1.<span class="me1">size</span><span class="br0">(</span><span class="br0">)</span><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> <span class="st0">&quot;b1[&quot;</span> <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> b1<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>
b1<span class="br0">[</span><span class="nu0">0</span><span class="br0">]</span> <span class="sy1">=</span> <span class="kw2">true</span><span class="sy4">;</span> <span class="co1">// &#36890;&#36807; bitset::reference &#20462;&#25913;&#39318;&#20301;</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;After setting bit 0, the bitset holds &quot;</span> <span class="sy1">&lt;&lt;</span> b1 <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">b1[0]: 0
b1[1]: 1
b1[2]: 0
b1[3]: 1
b1[4]: 0
b1[5]: 1
b1[6]: 0
b1[7]: 0
After setting bit 0, the bitset holds 00101011</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-utility-bitset-test.html"><span class="t-lines"><span>test</span></span></a></div>
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<td>&#35775;&#38382;&#29305;&#23450;&#20301;<br />
<span class="t-mark">(&#20844;&#24320;&#25104;&#21592;&#20989;&#25968;)</span></td>
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