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<h2><a name="for" id="for">for</a></h2>
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<p>
Syntax:
</p>
<pre class="c code c++" style="font-family:monospace;"> <span class="kw1">for</span><span class="br0">(</span> initialization<span class="sy0">;</span> test<span class="sy0">-</span>condition<span class="sy0">;</span> increment <span class="br0">)</span> <span class="br0">{</span>
statement<span class="sy0">-</span>list<span class="sy0">;</span>
<span class="br0">}</span></pre>
<p>
The for construct is a general looping mechanism consisting of 4 parts:
</p>
<pre class="c code c++" style="font-family:monospace;"> 1. <span class="me1">the</span> initialization<span class="sy0">,</span> which consists of 0 or more comma<span class="sy0">-</span>delimited variable
initialization statements
2. <span class="me1">the</span> test<span class="sy0">-</span>condition<span class="sy0">,</span> which is evaluated to determine <span class="kw1">if</span> the execution of
the <span class="kw1">for</span> loop will <span class="kw1">continue</span>
3. <span class="me1">the</span> increment<span class="sy0">,</span> which consists of <span class="nu0">0</span> or more comma<span class="sy0">-</span>delimited statements that
increment variables
4. <span class="me1">and</span> the statement<span class="sy0">-</span>list<span class="sy0">,</span> which consists of <span class="nu0">0</span> or more statements that will
be executed each time the loop is executed.</pre>
<p>
For example:
</p>
<pre class="c code c++" style="font-family:monospace;"> <span class="kw1">for</span><span class="br0">(</span> <span class="kw4">int</span> i <span class="sy0">=</span> <span class="nu0">0</span><span class="sy0">;</span> i <span class="sy0"><</span> <span class="nu0">10</span><span class="sy0">;</span> i<span class="sy0">++</span> <span class="br0">)</span> <span class="br0">{</span>
<a href="http://www.opengroup.org/onlinepubs/009695399/functions/cout.html"><span class="kw3">cout</span></a> <span class="sy0"><<</span> <span class="st0">"i is "</span> <span class="sy0"><<</span> i <span class="sy0"><<</span> endl<span class="sy0">;</span>
<span class="br0">}</span>
<span class="kw4">int</span> j<span class="sy0">,</span> k<span class="sy0">;</span>
<span class="kw1">for</span><span class="br0">(</span> j <span class="sy0">=</span> 0<span class="sy0">,</span> k <span class="sy0">=</span> <span class="nu0">10</span><span class="sy0">;</span>
j <span class="sy0"><</span> k<span class="sy0">;</span>
j<span class="sy0">++,</span> k<span class="sy0">--</span> <span class="br0">)</span> <span class="br0">{</span>
<a href="http://www.opengroup.org/onlinepubs/009695399/functions/cout.html"><span class="kw3">cout</span></a> <span class="sy0"><<</span> <span class="st0">"j is "</span> <span class="sy0"><<</span> j <span class="sy0"><<</span> <span class="st0">" and k is "</span> <span class="sy0"><<</span> k <span class="sy0"><<</span> endl<span class="sy0">;</span>
<span class="br0">}</span>
<span class="kw1">for</span><span class="br0">(</span> <span class="sy0">;</span> <span class="sy0">;</span> <span class="br0">)</span> <span class="br0">{</span>
<span class="co1">// loop forever!</span>
<span class="br0">}</span></pre>
<p>
Related Topics: <a href="../keywords/break.html" class="wikilink1" title="keywords:break">break</a>, <a href="../keywords/continue.html" class="wikilink1" title="keywords:continue">continue</a>, <a href="../keywords/do.html" class="wikilink1" title="keywords:do">do</a>, <a href="../keywords/if.html" class="wikilink1" title="keywords:if">if</a>, <a href="../keywords/while.html" class="wikilink1" title="keywords:while">while</a>
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