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<title>std::cmp_equal, cmp_not_equal, cmp_less, cmp_greater, cmp_less_equal, cmp_greater_equal</title>
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<h1 id="firstHeading" class="firstHeading"><span style="font-size:0.7em; line-height:130%">std::</span>cmp_equal, cmp_not_equal, cmp_less, cmp_greater, cmp_less_equal, cmp_greater_equal</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></span></div>
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<div>&#23450;&#20041;&#20110;&#22836;&#25991;&#20214; <code><a href="cpp-header-utility.html">&lt;utility&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> T, <span class="kw1">class</span> U <span class="sy1">&gt;</span><br />
<span class="kw4">constexpr</span> <span class="kw4">bool</span> cmp_equal<span class="br0">(</span> T t, U u <span class="br0">)</span> <span class="kw1">noexcept</span><span class="sy4">;</span></span></div>
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<td>(1)</td>
<td><span class="t-mark-rev t-since-cxx20">(C++20 &#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> T, <span class="kw1">class</span> U <span class="sy1">&gt;</span><br />
<span class="kw4">constexpr</span> <span class="kw4">bool</span> cmp_not_equal<span class="br0">(</span> T t, U u <span class="br0">)</span> <span class="kw1">noexcept</span><span class="sy4">;</span></span></div>
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<td>(2)</td>
<td><span class="t-mark-rev t-since-cxx20">(C++20 &#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> T, <span class="kw1">class</span> U <span class="sy1">&gt;</span><br />
<span class="kw4">constexpr</span> <span class="kw4">bool</span> cmp_less<span class="br0">(</span> T t, U u <span class="br0">)</span> <span class="kw1">noexcept</span><span class="sy4">;</span></span></div>
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<td>(3)</td>
<td><span class="t-mark-rev t-since-cxx20">(C++20 &#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> T, <span class="kw1">class</span> U <span class="sy1">&gt;</span><br />
<span class="kw4">constexpr</span> <span class="kw4">bool</span> cmp_greater<span class="br0">(</span> T t, U u <span class="br0">)</span> <span class="kw1">noexcept</span><span class="sy4">;</span></span></div>
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<td>(4)</td>
<td><span class="t-mark-rev t-since-cxx20">(C++20 &#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> T, <span class="kw1">class</span> U <span class="sy1">&gt;</span><br />
<span class="kw4">constexpr</span> <span class="kw4">bool</span> cmp_less_equal<span class="br0">(</span> T t, U u <span class="br0">)</span> <span class="kw1">noexcept</span><span class="sy4">;</span></span></div>
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<td>(5)</td>
<td><span class="t-mark-rev t-since-cxx20">(C++20 &#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> T, <span class="kw1">class</span> U <span class="sy1">&gt;</span><br />
<span class="kw4">constexpr</span> <span class="kw4">bool</span> cmp_greater_equal<span class="br0">(</span> T t, U u <span class="br0">)</span> <span class="kw1">noexcept</span><span class="sy4">;</span></span></div>
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<td>(6)</td>
<td><span class="t-mark-rev t-since-cxx20">(C++20 &#36215;)</span></td>
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<p>&#27604;&#36739;&#20108;&#20010;&#25972;&#25968; <code>t</code> &#19982; <code>u</code> &#30340;&#20540;&#12290;&#19981;&#21516;&#20110;&#20869;&#24314;&#27604;&#36739;&#36816;&#31639;&#31526;&#65292;&#36127;&#26377;&#31526;&#21495;&#25972;&#25968;&#22987;&#32456;&#27604;&#36739;<i>&#23567;&#20110;</i>&#65288;&#19988;<i>&#19981;&#31561;&#20110;</i>&#65289;&#26080;&#31526;&#21495;&#25972;&#25968;&#65306;&#35813;&#27604;&#36739;&#30456;&#23545;&#20110;&#26377;&#25439;&#25972;&#25968;&#36716;&#25442;&#26159;&#23433;&#20840;&#30340;&#12290;</p>
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<pre class="de1"><span class="sy2">-</span><span class="nu0">1</span> <span class="sy1">&gt;</span> 0u<span class="sy4">;</span> <span class="co1">// true</span>
std<span class="sy4">::</span><span class="me2">cmp_greater</span><span class="br0">(</span><span class="sy2">-</span><span class="nu0">1</span>, 0u<span class="br0">)</span><span class="sy4">;</span> <span class="co1">// false</span></pre></div>
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<p>&#33509; <code>T</code> &#25110; <code>U</code> &#19981;&#26159;&#26377;&#31526;&#21495;&#25110;&#26080;&#31526;&#21495;&#25972;&#25968;&#31867;&#22411;&#65288;&#21253;&#25324;&#26631;&#20934;&#25972;&#25968;&#31867;&#22411;&#19982;&#25193;&#23637;&#25972;&#25968;&#31867;&#22411;&#65289;&#65292;&#21017;&#20026;&#32534;&#35793;&#26102;&#38169;&#35823;&#12290;</p>
<h3><span class="mw-headline" id=".E5.8F.82.E6.95.B0">&#21442;&#25968;</span></h3>
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<td>t</td>
<td>-</td>
<td>&#24038;&#20391;&#21442;&#25968;</td>
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<td>u</td>
<td>-</td>
<td>&#21491;&#20391;&#21442;&#25968;</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>
<div class="t-li1"><span class="t-li">1)</span> &#33509; <code>t</code> &#31561;&#20110; <code>u</code> &#21017;&#20026; <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw2">true</span></span></span> &#12290;</div>
<div class="t-li1"><span class="t-li">2)</span> &#33509; <code>t</code> &#19981;&#31561;&#20110; <code>u</code> &#21017;&#20026; <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw2">true</span></span></span> &#12290;</div>
<div class="t-li1"><span class="t-li">3)</span> &#33509; <code>t</code> &#23567;&#20110; <code>u</code> &#21017;&#20026; <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw2">true</span></span></span> &#12290;</div>
<div class="t-li1"><span class="t-li">4)</span> &#33509; <code>t</code> &#22823;&#20110; <code>u</code> &#21017;&#20026; <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw2">true</span></span></span> &#12290;</div>
<div class="t-li1"><span class="t-li">5)</span> &#33509; <code>t</code> &#23567;&#20110;&#25110;&#31561;&#20110; <code>u</code> &#21017;&#20026; <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw2">true</span></span></span> &#12290;</div>
<div class="t-li1"><span class="t-li">6)</span> &#33509; <code>t</code> &#22823;&#20110;&#25110;&#31561;&#20110; <code>u</code> &#21017;&#20026; <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw2">true</span></span></span> &#12290;</div>
<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> T, <span class="kw1">class</span> U <span class="sy1">&gt;</span>
<span class="kw4">constexpr</span> <span class="kw4">bool</span> cmp_equal<span class="br0">(</span> T t, U u <span class="br0">)</span> <span class="kw1">noexcept</span>
<span class="br0">{</span>
<span class="kw1">using</span> UT <span class="sy1">=</span> <a href="cpp-types-make_unsigned.html"><span class="kw619">std::<span class="me2">make_unsigned_t</span></span></a><span class="sy1">&lt;</span>T<span class="sy1">&gt;</span><span class="sy4">;</span>
<span class="kw1">using</span> UU <span class="sy1">=</span> <a href="cpp-types-make_unsigned.html"><span class="kw619">std::<span class="me2">make_unsigned_t</span></span></a><span class="sy1">&lt;</span>U<span class="sy1">&gt;</span><span class="sy4">;</span>
<span class="kw1">if</span> <span class="kw4">constexpr</span> <span class="br0">(</span><a href="cpp-types-is_signed.html"><span class="kw517">std::<span class="me2">is_signed_v</span></span></a><span class="sy1">&lt;</span>T<span class="sy1">&gt;</span> <span class="sy1">==</span> <a href="cpp-types-is_signed.html"><span class="kw517">std::<span class="me2">is_signed_v</span></span></a><span class="sy1">&lt;</span>U<span class="sy1">&gt;</span><span class="br0">)</span>
<span class="kw1">return</span> t <span class="sy1">==</span> u<span class="sy4">;</span>
<span class="kw1">else</span> <span class="kw1">if</span> <span class="kw4">constexpr</span> <span class="br0">(</span><a href="cpp-types-is_signed.html"><span class="kw517">std::<span class="me2">is_signed_v</span></span></a><span class="sy1">&lt;</span>T<span class="sy1">&gt;</span><span class="br0">)</span>
<span class="kw1">return</span> t <span class="sy1">&lt;</span> <span class="nu0">0</span> <span class="sy4">?</span> <span class="kw2">false</span> <span class="sy4">:</span> UT<span class="br0">(</span>t<span class="br0">)</span> <span class="sy1">==</span> u<span class="sy4">;</span>
<span class="kw1">else</span>
<span class="kw1">return</span> u <span class="sy1">&lt;</span> <span class="nu0">0</span> <span class="sy4">?</span> <span class="kw2">false</span> <span class="sy4">:</span> t <span class="sy1">==</span> UU<span class="br0">(</span>u<span class="br0">)</span><span class="sy4">;</span>
<span class="br0">}</span>
<span class="kw1">template</span><span class="sy1">&lt;</span> <span class="kw1">class</span> T, <span class="kw1">class</span> U <span class="sy1">&gt;</span>
<span class="kw4">constexpr</span> <span class="kw4">bool</span> cmp_not_equal<span class="br0">(</span> T t, U u <span class="br0">)</span> <span class="kw1">noexcept</span>
<span class="br0">{</span>
<span class="kw1">return</span> <span class="sy3">!</span>cmp_equal<span class="br0">(</span>t, u<span class="br0">)</span><span class="sy4">;</span>
<span class="br0">}</span>
<span class="kw1">template</span><span class="sy1">&lt;</span> <span class="kw1">class</span> T, <span class="kw1">class</span> U <span class="sy1">&gt;</span>
<span class="kw4">constexpr</span> <span class="kw4">bool</span> cmp_less<span class="br0">(</span> T t, U u <span class="br0">)</span> <span class="kw1">noexcept</span>
<span class="br0">{</span>
<span class="kw1">using</span> UT <span class="sy1">=</span> <a href="cpp-types-make_unsigned.html"><span class="kw619">std::<span class="me2">make_unsigned_t</span></span></a><span class="sy1">&lt;</span>T<span class="sy1">&gt;</span><span class="sy4">;</span>
<span class="kw1">using</span> UU <span class="sy1">=</span> <a href="cpp-types-make_unsigned.html"><span class="kw619">std::<span class="me2">make_unsigned_t</span></span></a><span class="sy1">&lt;</span>U<span class="sy1">&gt;</span><span class="sy4">;</span>
<span class="kw1">if</span> <span class="kw4">constexpr</span> <span class="br0">(</span><a href="cpp-types-is_signed.html"><span class="kw517">std::<span class="me2">is_signed_v</span></span></a><span class="sy1">&lt;</span>T<span class="sy1">&gt;</span> <span class="sy1">==</span> <a href="cpp-types-is_signed.html"><span class="kw517">std::<span class="me2">is_signed_v</span></span></a><span class="sy1">&lt;</span>U<span class="sy1">&gt;</span><span class="br0">)</span>
<span class="kw1">return</span> t <span class="sy1">&lt;</span> u<span class="sy4">;</span>
<span class="kw1">else</span> <span class="kw1">if</span> <span class="kw4">constexpr</span> <span class="br0">(</span><a href="cpp-types-is_signed.html"><span class="kw517">std::<span class="me2">is_signed_v</span></span></a><span class="sy1">&lt;</span>T<span class="sy1">&gt;</span><span class="br0">)</span>
<span class="kw1">return</span> t <span class="sy1">&lt;</span> <span class="nu0">0</span> <span class="sy4">?</span> <span class="kw2">true</span> <span class="sy4">:</span> UT<span class="br0">(</span>t<span class="br0">)</span> <span class="sy1">&lt;</span> u<span class="sy4">;</span>
<span class="kw1">else</span>
<span class="kw1">return</span> u <span class="sy1">&lt;</span> <span class="nu0">0</span> <span class="sy4">?</span> <span class="kw2">false</span> <span class="sy4">:</span> t <span class="sy1">&lt;</span> UU<span class="br0">(</span>u<span class="br0">)</span><span class="sy4">;</span>
<span class="br0">}</span>
<span class="kw1">template</span><span class="sy1">&lt;</span> <span class="kw1">class</span> T, <span class="kw1">class</span> U <span class="sy1">&gt;</span>
<span class="kw4">constexpr</span> <span class="kw4">bool</span> cmp_greater<span class="br0">(</span> T t, U u <span class="br0">)</span> <span class="kw1">noexcept</span>
<span class="br0">{</span>
<span class="kw1">return</span> cmp_less<span class="br0">(</span>u, t<span class="br0">)</span><span class="sy4">;</span>
<span class="br0">}</span>
<span class="kw1">template</span><span class="sy1">&lt;</span> <span class="kw1">class</span> T, <span class="kw1">class</span> U <span class="sy1">&gt;</span>
<span class="kw4">constexpr</span> <span class="kw4">bool</span> cmp_less_equal<span class="br0">(</span> T t, U u <span class="br0">)</span> <span class="kw1">noexcept</span>
<span class="br0">{</span>
<span class="kw1">return</span> <span class="sy3">!</span>cmp_greater<span class="br0">(</span>t, u<span class="br0">)</span><span class="sy4">;</span>
<span class="br0">}</span>
<span class="kw1">template</span><span class="sy1">&lt;</span> <span class="kw1">class</span> T, <span class="kw1">class</span> U <span class="sy1">&gt;</span>
<span class="kw4">constexpr</span> <span class="kw4">bool</span> cmp_greater_equal<span class="br0">(</span> T t, U u <span class="br0">)</span> <span class="kw1">noexcept</span>
<span class="br0">{</span>
<span class="kw1">return</span> <span class="sy3">!</span>cmp_less<span class="br0">(</span>t, u<span class="br0">)</span><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>&#36825;&#20123;&#20989;&#25968;&#19981;&#33021;&#29992;&#20110;&#27604;&#36739;<a href="cpp-language-enum.html">&#26522;&#20030;</a>&#65288;&#21253;&#25324; <a href="cpp-types-byte.html"><tt>std::byte</tt></a> &#65289;&#12289; <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw4">char</span></span></span> &#12289; <span class="t-c"><span class="mw-geshi cpp source-cpp">char8_t</span></span> &#12289; <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw4">char16_t</span></span></span> &#12289; <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw4">char32_t</span></span></span> &#12289; <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw4">wchar_t</span></span></span> &#21450; <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw4">bool</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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