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<h1 id="firstHeading" class="firstHeading">&#33258;&#22686;/&#33258;&#20943;&#36816;&#31639;&#31526;</h1>
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<div id="contentSub"><span class="subpages">&lt; <a href="c.html">c</a>&lrm; | <a href="c-language.html">language</a></span></div>
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<p>&#33258;&#22686;/&#33258;&#20943;&#36816;&#31639;&#31526;&#26159;&#20351;&#23545;&#35937;&#30340;&#20540;&#22686;&#21152;/&#20943;&#23569; 1 &#30340;&#19968;&#20803;&#36816;&#31639;&#31526;&#12290;</p>
<p>&#23427;&#20204;&#33021;&#25317;&#26377;&#21518;&#32512;&#24418;&#24335;&#65306;</p>
<table class="t-sdsc-begin">
<tr>
<td colspan="10" class="t-sdsc-sep"></td>
</tr>
<tr class="t-sdsc">
<td class="t-sdsc-nopad"><span class="t-spar">expr</span> <code><b>++</b></code></td>
<td class="t-sdsc-nopad"></td>
<td class="t-sdsc-nopad"></td>
</tr>
<tr>
<td colspan="10" class="t-sdsc-sep"></td>
</tr>
<tr class="t-sdsc">
<td class="t-sdsc-nopad"><span class="t-spar">expr</span> <code><b>--</b></code></td>
<td class="t-sdsc-nopad"></td>
<td class="t-sdsc-nopad"></td>
</tr>
<tr>
<td colspan="10" class="t-sdsc-sep"></td>
</tr>
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<p>&#36824;&#26377;&#21069;&#32512;&#24418;&#24335;&#65306;</p>
<table class="t-sdsc-begin">
<tr>
<td colspan="10" class="t-sdsc-sep"></td>
</tr>
<tr class="t-sdsc">
<td class="t-sdsc-nopad"><code><b>++</b></code> <span class="t-spar">expr</span></td>
<td class="t-sdsc-nopad"></td>
<td class="t-sdsc-nopad"></td>
</tr>
<tr>
<td colspan="10" class="t-sdsc-sep"></td>
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<td class="t-sdsc-nopad"><code><b>--</b></code> <span class="t-spar">expr</span></td>
<td class="t-sdsc-nopad"></td>
<td class="t-sdsc-nopad"></td>
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<p>&#21069;&#32512;&#21644;&#21518;&#32512;&#33258;&#22686;&#25110;&#33258;&#20943;&#30340;&#36816;&#31639;&#25968; <span class="t-spar">expr</span> &#24517;&#39035;&#20026;<a href="c-language-type.html" class="mw-redirect">&#25972;&#25968;&#31867;&#22411;</a>&#65288;&#21253;&#21547; <code>_Bool</code> &#21644;&#26522;&#20030;&#65289;&#12289;&#23454;&#28014;&#28857;&#31867;&#22411;&#25110;&#25351;&#38024;&#31867;&#22411;&#30340;<a href="c-language-value_category.html">&#21487;&#20462;&#25913;&#24038;&#20540;</a>&#12290;&#23427;&#33021;&#20026; cvr &#38480;&#23450;&#12289;&#26080;&#38480;&#23450;&#25110;&#20026;<a href="c-language-atomic.html">&#21407;&#23376;</a>&#12290;</p>
<p>&#21518;&#32512;&#33258;&#22686;&#21644;&#33258;&#20943;&#36816;&#31639;&#31526;&#30340;&#32467;&#26524;&#26159; <span class="t-spar">expr</span> &#30340;&#20540;&#12290;</p>
<p>&#21069;&#32512;&#33258;&#22686;&#36816;&#31639;&#31526;&#30340;&#32467;&#26524;&#26159;&#23558;&#20540; <code>1</code> &#21152;&#21040; <span class="t-spar">expr</span> &#30340;&#20540;&#30340;&#32467;&#26524;&#65306;&#34920;&#36798;&#24335; <span class="t-c"><span class="mw-geshi c source-c"><span class="sy2">++</span>e</span></span> &#31561;&#20215;&#20110; <span class="t-c"><span class="mw-geshi c source-c">e<span class="sy2">+</span><span class="sy1">=</span><span class="nu0">1</span></span></span> &#12290;&#21069;&#32512;&#33258;&#20943;&#36816;&#31639;&#31526;&#30340;&#32467;&#26524;&#20174; <span class="t-spar">expr</span> &#20943;&#21435;&#20540; <code>1</code> &#30340;&#32467;&#26524;&#65306;&#34920;&#36798;&#24335; <span class="t-c"><span class="mw-geshi c source-c"><span class="sy2">--</span>e</span></span> &#31561;&#20215;&#20110; <span class="t-c"><span class="mw-geshi c source-c">e<span class="sy2">-</span><span class="sy1">=</span><span class="nu0">1</span></span></span> &#12290;</p>
<p>&#33258;&#22686;&#36816;&#31639;&#31526;&#21457;&#21160;&#21152;&#30456;&#24212;&#31867;&#22411;&#30340;&#20540; <code>1</code> &#21040;&#36816;&#31639;&#25968;&#30340;&#21103;&#25928;&#24212;&#12290;&#33258;&#20943;&#36816;&#31639;&#31526;&#21457;&#21160;&#20174;&#36816;&#31639;&#25968;&#20943;&#21435;&#30456;&#24212;&#31867;&#22411;&#30340;&#20540; <code>1</code> &#30340;&#21103;&#25928;&#24212;&#12290;&#21516;&#20854;&#20182;&#21103;&#25928;&#24212;&#65292;&#36825;&#20123;&#25805;&#20316;&#22312;&#19979;&#20010;<a href="c-language-eval_order.html">&#24207;&#21015;&#28857;</a>&#25110;&#37027;&#20043;&#21069;&#23436;&#25104;&#12290;</p>
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<div class="c source-c">
<pre class="de1"><span class="kw4">int</span> a <span class="sy1">=</span> <span class="nu0">1</span><span class="sy4">;</span>
<span class="kw4">int</span> b <span class="sy1">=</span> a<span class="sy2">++</span><span class="sy4">;</span> <span class="co1">// &#23384;&#20648; 1+a &#65288;&#21363; 2 &#65289;&#21040; a</span>
<span class="co1">// &#36820;&#22238; a &#30340;&#20540;&#65288;&#21363; 1 &#65289;</span>
<span class="co1">// &#27492;&#34892;&#21518;&#65292; b == 1 &#32780; a == 2</span>
a <span class="sy1">=</span> <span class="nu0">1</span><span class="sy4">;</span>
<span class="kw4">int</span> c <span class="sy1">=</span> <span class="sy2">++</span>a<span class="sy4">;</span> <span class="co1">// &#23384;&#20648; 1+a &#65288;&#21363; 2 &#65289;&#21040; a</span>
<span class="co1">// &#36820;&#22238; 1+a &#65288;&#21363; 2 &#65289;</span>
<span class="co1">// &#27492;&#34892;&#21518;&#65292; c == 2 &#32780; a == 2</span></pre></div>
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<table class="t-rev-begin">
<tr class="t-rev t-since-c11">
<td>
<p>&#20219;&#20309;<a href="c-language-atomic.html">&#21407;&#23376;&#23545;&#35937;</a>&#19978;&#30340;&#21518;&#33258;&#22686;&#25110;&#21518;&#33258;&#20943;&#36816;&#31639;&#31526;&#65292;&#26159;&#25317;&#26377; <span class="t-lc"><a href="c-atomic-memory_order.html">memory_order_seq_cst</a></span> &#20869;&#23384;&#39034;&#24207;&#30340;&#21407;&#23376;&#35835;&#20462;&#25913;&#20889;&#25805;&#20316;&#12290;</p>
</td>
<td><span class="t-mark-rev t-since-c11">(C11 &#36215;)</span></td>
</tr>
</table>
<p>&#25351;&#38024;&#31639;&#26415;&#19978;&#30340;&#38480;&#21046;&#65292;&#36824;&#26377;&#24212;&#29992;&#20110;&#36816;&#31639;&#25968;&#30340;&#38544;&#24335;&#36716;&#25442;&#35265;<a href="c-language-operator_arithmetic.html">&#31639;&#26415;&#36816;&#31639;&#31526;</a>&#12290;</p>
<h3><span class="mw-headline" id=".E6.B3.A8.E6.84.8F">&#27880;&#24847;</span></h3>
<p>&#22240;&#20026;&#28041;&#21450;&#21103;&#25928;&#24212;&#65292;&#24517;&#39035;&#35880;&#24910;&#22320;&#20351;&#29992;&#33258;&#22686;&#21644;&#33258;&#20943;&#36816;&#31639;&#31526;&#65292;&#20197;&#36991;&#20813;&#36829;&#32972;<a href="c-language-eval_order.html">&#23450;&#24207;&#35268;&#21017;</a>&#25152;&#33268;&#30340;&#26410;&#23450;&#20041;&#34892;&#20026;&#12290;</p>
<p>&#33258;&#22686;/&#33258;&#20943;&#36816;&#31639;&#31526;&#19981;&#23545;&#22797;&#25968;&#25110;&#34394;&#25968;&#31867;&#22411;&#23450;&#20041;&#65306;&#21152;/&#20943;&#23454;&#25968; 1 &#30340;&#36890;&#24120;&#23450;&#20041;&#23545;&#34394;&#25968;&#20250;&#26080;&#25928;&#65292;&#32780;&#20351;&#20043;&#23545;&#34394;&#25968;&#21152;/&#20943; <code>i</code> &#20294;&#23545;&#22797;&#25968;&#21152;/&#20943; <code>1</code> &#65292;&#20250;&#20351;&#24471;&#22788;&#29702; <code>0+yi</code> &#21644; <code>yi</code> &#30340;&#26041;&#24335;&#26377;&#21035;&#12290;</p>
<p>&#19981;&#21516;&#20110; C++ &#65288;&#21644; C &#30340;&#26576;&#20123;&#23454;&#29616;&#65289;&#65292;&#33258;&#22686;/&#33258;&#20943;&#36816;&#31639;&#31526;&#33258;&#36523;&#20915;&#38750;&#24038;&#20540;&#65306; <span class="t-c"><span class="mw-geshi c source-c"><span class="sy3">&amp;</span><span class="sy2">++</span>a</span></span> &#26159;&#38750;&#27861;&#30340;&#12290;</p>
<h3><span class="mw-headline" id=".E7.A4.BA.E4.BE.8B">&#31034;&#20363;</span></h3>
<div class="t-example">
<div class="t-example-live-link"></div>
<div dir="ltr" class="mw-geshi" style="text-align: left;">
<div class="c source-c">
<pre class="de1"><span class="co2">#include &lt;stdlib.h&gt;</span>
<span class="co2">#include &lt;stdio.h&gt;</span>
<span class="kw4">int</span> main<span class="br0">(</span><span class="kw4">void</span><span class="br0">)</span> <span class="br0">{</span>
<span class="kw4">int</span> a <span class="sy1">=</span> <span class="nu0">1</span><span class="sy4">;</span>
<span class="kw4">int</span> b <span class="sy1">=</span> <span class="nu0">1</span><span class="sy4">;</span>
<a href="c-io-fprintf.html"><span class="kw851">printf</span></a><span class="br0">(</span><span class="st0">&quot;<span class="es1">\n</span>&quot;</span><span class="br0">)</span><span class="sy4">;</span>
<a href="c-io-fprintf.html"><span class="kw851">printf</span></a><span class="br0">(</span><span class="st0">&quot;original values: a == %d, b == %d<span class="es1">\n</span>&quot;</span>, a, b<span class="br0">)</span><span class="sy4">;</span>
<a href="c-io-fprintf.html"><span class="kw851">printf</span></a><span class="br0">(</span><span class="st0">&quot;result of postfix operators: a++ == %d, b-- == %d<span class="es1">\n</span>&quot;</span>, a<span class="sy2">++</span>, b<span class="sy2">--</span><span class="br0">)</span><span class="sy4">;</span>
<a href="c-io-fprintf.html"><span class="kw851">printf</span></a><span class="br0">(</span><span class="st0">&quot;after postfix operators applied: a == %d, b == %d<span class="es1">\n</span>&quot;</span>, a, b<span class="br0">)</span><span class="sy4">;</span>
<span class="co1">// &#37325;&#32622; a &#19982; b &#12290;</span>
a <span class="sy1">=</span> <span class="nu0">1</span><span class="sy4">;</span>
b <span class="sy1">=</span> <span class="nu0">1</span><span class="sy4">;</span>
<a href="c-io-fprintf.html"><span class="kw851">printf</span></a><span class="br0">(</span><span class="st0">&quot;<span class="es1">\n</span>&quot;</span><span class="br0">)</span><span class="sy4">;</span>
<a href="c-io-fprintf.html"><span class="kw851">printf</span></a><span class="br0">(</span><span class="st0">&quot;original values: a == %d, b == %d<span class="es1">\n</span>&quot;</span>, a, b<span class="br0">)</span><span class="sy4">;</span>
<a href="c-io-fprintf.html"><span class="kw851">printf</span></a><span class="br0">(</span><span class="st0">&quot;result of prefix operators: ++a == %d, --b == %d<span class="es1">\n</span>&quot;</span>, <span class="sy2">++</span>a, <span class="sy2">--</span>b<span class="br0">)</span><span class="sy4">;</span>
<a href="c-io-fprintf.html"><span class="kw851">printf</span></a><span class="br0">(</span><span class="st0">&quot;after prefix operators applied: a == %d, b == %d<span class="es1">\n</span>&quot;</span>, a, b<span class="br0">)</span><span class="sy4">;</span>
<span class="br0">}</span></pre></div>
</div>
<p>&#36755;&#20986;&#65306;</p>
<div dir="ltr" class="mw-geshi" style="text-align: left;">
<div class="text source-text">
<pre class="de1">original values: a == 1, b == 1
result of postfix operators: a++ == 1, b-- == 1
after postfix operators applied: a == 2, b == 0
original values: a == 1, b == 1
result of prefix operators: ++a == 2, --b == 0
after prefix operators applied: a == 2, b == 0</pre></div>
</div>
</div>
<h3><span class="mw-headline" id=".E5.BC.95.E7.94.A8">&#24341;&#29992;</span></h3>
<div class="t-ref-std-11">
<ul>
<li>C11 &#26631;&#20934;&#65288;ISO/IEC 9899:2011&#65289;&#65306;</li>
</ul>
<dl>
<dd>
<ul>
<li>6.5.2.4 Postfix increment and decrement operators (p: 85)</li>
</ul>
</dd>
</dl>
<dl>
<dd>
<ul>
<li>6.5.3.1 Prefix increment and decrement operators (p: 88)</li>
</ul>
</dd>
</dl>
<div class="t-ref-std-c99">
<ul>
<li>C99 &#26631;&#20934;&#65288;ISO/IEC 9899:1999&#65289;&#65306;</li>
</ul>
<dl>
<dd>
<ul>
<li>6.5.2.4 Postfix increment and decrement operators (p: 75)</li>
</ul>
</dd>
</dl>
<dl>
<dd>
<ul>
<li>6.5.3.1 Prefix increment and decrement operators (p: 78)</li>
</ul>
</dd>
</dl>
<div class="t-ref-std-c89">
<ul>
<li>C89/C90 &#26631;&#20934;&#65288;ISO/IEC 9899:1990&#65289;&#65306;</li>
</ul>
<dl>
<dd>
<ul>
<li>3.3.2.4 Postfix increment and decrement operators</li>
</ul>
</dd>
</dl>
<dl>
<dd>
<ul>
<li>3.3.3.1 Prefix increment and decrement operators</li>
</ul>
</dd>
</dl>
</div>
<h3><span class="mw-headline" id=".E5.8F.82.E9.98.85">&#21442;&#38405;</span></h3>
<p><a href="c-language-operator_precedence.html">&#36816;&#31639;&#31526;&#20248;&#20808;&#32423;</a></p>
<table class="wikitable">
<tr style="text-align:center">
<th colspan="7">&#24120;&#29992;&#36816;&#31639;&#31526;</th>
</tr>
<tr style="text-align:center">
<td><a href="c-language-operator_assignment.html">&#36171;&#20540;</a></td>
<td><strong class="selflink">&#33258;&#22686;<br />
&#33258;&#20943;</strong></td>
<td><a href="c-language-operator_arithmetic.html">&#31639;&#26415;</a></td>
<td><a href="c-language-operator_logical.html">&#36923;&#36753;</a></td>
<td><a href="c-language-operator_comparison.html">&#27604;&#36739;</a></td>
<td><a href="c-language-operator_member_access.html">&#25104;&#21592;<br />
&#35775;&#38382;</a></td>
<td><a href="c-language-operator_other.html">&#20854;&#20182;</a></td>
</tr>
<tr style="text-align:center">
<td>
<p><span class="t-c"><span class="mw-geshi c source-c">a <span class="sy1">=</span> b<br />
a <span class="sy2">+</span><span class="sy1">=</span> b<br />
a <span class="sy2">-</span><span class="sy1">=</span> b<br />
a <span class="sy2">*</span><span class="sy1">=</span> b<br />
a <span class="sy2">/</span><span class="sy1">=</span> b<br />
a <span class="sy2">%</span><span class="sy1">=</span> b<br />
a <span class="sy3">&amp;</span><span class="sy1">=</span> b<br />
a <span class="sy3">|</span><span class="sy1">=</span> b<br />
a <span class="sy3">^</span><span class="sy1">=</span> b<br />
a <span class="sy1">&lt;&lt;=</span> b<br />
a <span class="sy1">&gt;&gt;=</span> b</span></span></p>
</td>
<td>
<p><span class="t-c"><span class="mw-geshi c source-c"><span class="sy2">++</span>a<br />
<span class="sy2">--</span>a<br />
a<span class="sy2">++</span><br />
a<span class="sy2">--</span></span></span></p>
</td>
<td>
<p><span class="t-c"><span class="mw-geshi c source-c"><span class="sy2">+</span>a<br />
<span class="sy2">-</span>a<br />
a <span class="sy2">+</span> b<br />
a <span class="sy2">-</span> b<br />
a <span class="sy2">*</span> b<br />
a <span class="sy2">/</span> b<br />
a <span class="sy2">%</span> b<br />
~a<br />
a <span class="sy3">&amp;</span> b<br />
a <span class="sy3">|</span> b<br />
a <span class="sy3">^</span> b<br />
a <span class="sy1">&lt;&lt;</span> b<br />
a <span class="sy1">&gt;&gt;</span> b</span></span></p>
</td>
<td>
<p><span class="t-c"><span class="mw-geshi c source-c"><span class="sy3">!</span>a<br />
a <span class="sy3">&amp;&amp;</span> b<br />
a <span class="sy3">||</span> b</span></span></p>
</td>
<td>
<p><span class="t-c"><span class="mw-geshi c source-c">a <span class="sy1">==</span> b<br />
a <span class="sy3">!</span><span class="sy1">=</span> b<br />
a <span class="sy1">&lt;</span> b<br />
a <span class="sy1">&gt;</span> b<br />
a <span class="sy1">&lt;=</span> b<br />
a <span class="sy1">&gt;=</span> b</span></span></p>
</td>
<td>
<p><span class="t-c"><span class="mw-geshi c source-c">a<span class="br0">[</span>b<span class="br0">]</span><br />
<span class="sy2">*</span>a<br />
<span class="sy3">&amp;</span>a<br />
a<span class="sy2">-</span><span class="sy1">&gt;</span>b<br />
a.<span class="me1">b</span></span></span></p>
</td>
<td>
<p><span class="t-c"><span class="mw-geshi c source-c">a<span class="br0">(</span>...<span class="br0">)</span><br />
a, b<br />
<span class="br0">(</span>type<span class="br0">)</span> a<br />
<span class="sy4">?</span> <span class="sy4">:</span><br />
<span class="kw4">sizeof</span><br />
_Alignof</span></span> <span class="t-mark-rev t-since-c11">(C11 &#36215;)</span></p>
</td>
</tr>
</table>
<table class="t-dsc-begin"></table>
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<div class="visualClear"></div>
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