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<h1 id="firstHeading" class="firstHeading"><span style="font-size:0.7em; line-height:130%">std::</span>ratio_greater_equal</h1>
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<div id="contentSub"><span class="subpages">&lt; <a href="cpp.html">cpp</a>&lrm; | <a href="cpp-numeric.html">numeric</a>&lrm; | <a href="cpp-numeric-ratio.html">ratio</a></span></div>
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<div>&#23450;&#20041;&#20110;&#22836;&#25991;&#20214; <code><a href="cpp-header-ratio.html">&lt;ratio&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> R1, <span class="kw1">class</span> R2 <span class="sy1">&gt;</span><br />
<span class="kw1">struct</span> ratio_greater_equal <span class="sy4">:</span> <a href="cpp-types-integral_constant.html"><span class="kw647">std::<span class="me2">integral_constant</span></span></a><span class="sy1">&lt;</span><span class="kw4">bool</span>, <span class="coMULTI">/* see below */</span><span class="sy1">&gt;</span> <span class="br0">{</span> <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></td>
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<p>&#33509;&#27604;&#20363; <code>R1</code> &#22823;&#20110;&#25110;&#31561;&#20110;&#27604;&#20363; <code>R2</code> &#65292;&#21017;&#25552;&#20379;&#31561;&#20110; <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw2">true</span></span></span> &#30340;&#25104;&#21592;&#24120;&#37327; <code>value</code> &#12290;&#21542;&#21017; <code>value</code> &#31561;&#20110; <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw2">false</span></span></span> &#12290;</p>
<h3><span class="mw-headline" id=".E8.BE.85.E5.8A.A9.E5.8F.98.E9.87.8F.E6.A8.A1.E6.9D.BF">&#36741;&#21161;&#21464;&#37327;&#27169;&#26495;</span></h3>
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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> R1, <span class="kw1">class</span> R2 <span class="sy1">&gt;</span><br />
<span class="kw1">inline</span> <span class="kw4">constexpr</span> <span class="kw4">bool</span> ratio_greater_equal_v <span class="sy1">=</span> ratio_greater_equal<span class="sy1">&lt;</span>R1, R2<span class="sy1">&gt;</span><span class="sy4">::</span><span class="me2">value</span><span class="sy4">;</span></span></div>
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<td><span class="t-mark-rev t-since-cxx17">(C++17 &#36215;)</span></td>
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<h2><span class="mw-headline" id=".E7.BB.A7.E6.89.BF.E8.87.AA_std::integral_constant">&#32487;&#25215;&#33258; <a href="cpp-types-integral_constant.html"><span style="font-size:0.7em; line-height:130%">std::</span>integral_constant</a></span></h2>
<h3><span class="mw-headline" id=".E6.88.90.E5.91.98.E5.B8.B8.E9.87.8F">&#25104;&#21592;&#24120;&#37327;</span></h3>
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<div><span class="t-lines"><span>value</span></span></div>
<div><span class="t-lines"><span><span class="t-cmark">[&#38745;&#24577;]</span></span></span></div>
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<td>&#33509; <span class="t-c"><span class="mw-geshi cpp source-cpp">R1<span class="sy4">::</span><span class="me2">num</span> <span class="sy2">*</span> R2<span class="sy4">::</span><span class="me2">den</span> <span class="sy1">&gt;=</span> R2<span class="sy4">::</span><span class="me2">num</span> <span class="sy2">*</span> R1<span class="sy4">::</span><span class="me2">den</span></span></span> &#25110;&#36991;&#20813;&#28322;&#20986;&#30340;&#31561;&#20215;&#34920;&#36798;&#24335;&#25104;&#31435;&#65292;&#21017;&#20026; <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw2">true</span></span></span> &#65292;&#21542;&#21017;&#20026; <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw2">false</span></span></span><br />
<span class="t-mark">(&#20844;&#24320;&#38745;&#24577;&#25104;&#21592;&#24120;&#37327;)</span></td>
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<h3><span class="mw-headline" id=".E6.88.90.E5.91.98.E5.87.BD.E6.95.B0">&#25104;&#21592;&#20989;&#25968;</span></h3>
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<div><span class="t-lines"><span>operator bool</span></span></div>
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<td>&#36716;&#25442;&#23545;&#35937;&#20026; <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw4">bool</span></span></span> &#65292;&#36820;&#22238; <code>value</code><br />
<span class="t-mark">(&#20844;&#24320;&#25104;&#21592;&#20989;&#25968;)</span></td>
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<div><span class="t-lines"><span>operator()</span></span></div>
<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx14">(C++14)</span></span></span></div>
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<td>&#36820;&#22238; <code>value</code><br />
<span class="t-mark">(&#20844;&#24320;&#25104;&#21592;&#20989;&#25968;)</span></td>
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<h3><span class="mw-headline" id=".E6.88.90.E5.91.98.E7.B1.BB.E5.9E.8B">&#25104;&#21592;&#31867;&#22411;</span></h3>
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<td><code>value_type</code></td>
<td><code>bool</code></td>
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<td><code>type</code></td>
<td><span class="t-c"><span class="mw-geshi cpp source-cpp"><a href="cpp-types-integral_constant.html"><span class="kw647">std::<span class="me2">integral_constant</span></span></a><span class="sy1">&lt;</span><span class="kw4">bool</span>, value<span class="sy1">&gt;</span></span></span></td>
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<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;ratio&gt;</span>
<span class="co2">#include &lt;iostream&gt;</span>
<span class="kw4">auto</span> main<span class="br0">(</span><span class="br0">)</span> <span class="sy2">-</span><span class="sy1">&gt;</span> <span class="kw4">int</span>
<span class="br0">{</span>
static_assert<span class="br0">(</span>std<span class="sy4">::</span><span class="me2">ratio_greater_equal</span><span class="sy1">&lt;</span>
<a href="cpp-numeric-ratio-ratio.html"><span class="kw1522">std::<span class="me2">ratio</span></span></a><span class="sy1">&lt;</span><span class="nu0">2</span>, <span class="nu0">3</span><span class="sy1">&gt;</span>,
<a href="cpp-numeric-ratio-ratio.html"><span class="kw1522">std::<span class="me2">ratio</span></span></a><span class="sy1">&lt;</span><span class="nu0">2</span>, <span class="nu0">3</span><span class="sy1">&gt;&gt;</span><span class="sy4">::</span><span class="me2">value</span>, <span class="st0">&quot;2/3 &gt;= 2/3&quot;</span><span class="br0">)</span><span class="sy4">;</span>
<span class="kw1">if</span> <span class="br0">(</span>std<span class="sy4">::</span><span class="me2">ratio_greater_equal</span><span class="sy1">&lt;</span>
<a href="cpp-numeric-ratio-ratio.html"><span class="kw1522">std::<span class="me2">ratio</span></span></a><span class="sy1">&lt;</span><span class="nu0">2</span>,<span class="nu0">1</span><span class="sy1">&gt;</span>, <a href="cpp-numeric-ratio-ratio.html"><span class="kw1522">std::<span class="me2">ratio</span></span></a><span class="sy1">&lt;</span><span class="nu0">1</span>, <span class="nu0">2</span><span class="sy1">&gt;&gt;</span><span class="sy4">::</span><span class="me2">value</span><span class="br0">)</span> <span class="br0">{</span>
<a href="cpp-io-cout.html"><span class="kw1756">std::<span class="me2">cout</span></span></a> <span class="sy1">&lt;&lt;</span> <span class="st0">&quot;2/1 &gt;= 1/2&quot;</span> <span class="st0">&quot;<span class="es1">\n</span>&quot;</span><span class="sy4">;</span>
<span class="br0">}</span>
<span class="kw1">if</span> <span class="br0">(</span>std<span class="sy4">::</span><span class="me2">ratio_greater_equal</span><span class="sy1">&lt;</span>
<a href="cpp-numeric-ratio-ratio.html"><span class="kw1522">std::<span class="me2">ratio</span></span></a><span class="sy1">&lt;</span><span class="nu0">1</span>,<span class="nu0">2</span><span class="sy1">&gt;</span>, <a href="cpp-numeric-ratio-ratio.html"><span class="kw1522">std::<span class="me2">ratio</span></span></a><span class="sy1">&lt;</span><span class="nu0">1</span>, <span class="nu0">2</span><span class="sy1">&gt;&gt;</span><span class="sy4">::</span><span class="me2">value</span><span class="br0">)</span> <span class="br0">{</span>
<a href="cpp-io-cout.html"><span class="kw1756">std::<span class="me2">cout</span></span></a> <span class="sy1">&lt;&lt;</span> <span class="st0">&quot;1/2 &gt;= 1/2&quot;</span> <span class="st0">&quot;<span class="es1">\n</span>&quot;</span><span class="sy4">;</span>
<span class="br0">}</span>
<span class="co1">// C++17 &#36215;</span>
static_assert<span class="br0">(</span>std<span class="sy4">::</span><span class="me2">ratio_greater_equal_v</span><span class="sy1">&lt;</span>
<a href="cpp-numeric-ratio-ratio.html"><span class="kw1522">std::<span class="me2">ratio</span></span></a><span class="sy1">&lt;</span><span class="nu0">999</span><span class="st0">&#39;999, 1&#39;</span><span class="nu8">000</span><span class="st0">&#39;000&gt;,
std::ratio&lt;999&#39;</span><span class="nu0">998</span>, <span class="nu0">999</span><span class="st0">&#39;999&gt;&gt; );
if constexpr (std::ratio_greater_equal_v&lt;
std::ratio&lt;999&#39;</span><span class="nu0">999</span>, <span class="nu0">1</span><span class="st0">&#39;000&#39;</span><span class="nu8">000</span><span class="sy1">&gt;</span>,
<a href="cpp-numeric-ratio-ratio.html"><span class="kw1522">std::<span class="me2">ratio</span></span></a><span class="sy1">&lt;</span><span class="nu0">999</span><span class="st0">&#39;998, 999&#39;</span><span class="nu0">999</span><span class="sy1">&gt;&gt;</span><span class="br0">)</span> <span class="br0">{</span>
<a href="cpp-io-cout.html"><span class="kw1756">std::<span class="me2">cout</span></span></a> <span class="sy1">&lt;&lt;</span> <span class="st0">&quot;999&#39;999/1&#39;000&#39;000 &gt;= 999&#39;998/999&#39;999&quot;</span> <span class="st0">&quot;<span class="es1">\n</span>&quot;</span><span class="sy4">;</span>
<span class="br0">}</span>
<span class="kw1">if</span> <span class="kw4">constexpr</span> <span class="br0">(</span>std<span class="sy4">::</span><span class="me2">ratio_greater_equal_v</span><span class="sy1">&lt;</span>
<a href="cpp-numeric-ratio-ratio.html"><span class="kw1522">std::<span class="me2">ratio</span></span></a><span class="sy1">&lt;</span><span class="nu0">999</span><span class="st0">&#39;999, 1&#39;</span><span class="nu8">000</span><span class="st0">&#39;000&gt;,
std::ratio&lt;999&#39;</span><span class="nu0">999</span>, <span class="nu0">1</span><span class="st0">&#39;000&#39;</span><span class="nu8">000</span><span class="sy1">&gt;&gt;</span><span class="br0">)</span> <span class="br0">{</span>
<a href="cpp-io-cout.html"><span class="kw1756">std::<span class="me2">cout</span></span></a> <span class="sy1">&lt;&lt;</span> <span class="st0">&quot;999&#39;999/1&#39;000&#39;000 &gt;= 999&#39;999/1&#39;000&#39;000&quot;</span> <span class="st0">&quot;<span class="es1">\n</span>&quot;</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">2/1 &gt;= 1/2
1/2 &gt;= 1/2
999&#39;999/1&#39;000&#39;000 &gt;= 999&#39;998/999&#39;999
999&#39;999/1&#39;000&#39;000 &gt;= 999&#39;999/1&#39;000&#39;000</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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