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if [C++ Reference]
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<h2><a name="if" id="if">if</a></h2>
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<p>
Syntax:
</p>
<pre class="c code c++" style="font-family:monospace;"> <span class="kw1">if</span><span class="br0">(</span> conditionA <span class="br0">)</span> <span class="br0">{</span>
statement<span class="sy0">-</span>listA<span class="sy0">;</span>
<span class="br0">}</span>
<span class="kw1">else</span> <span class="kw1">if</span><span class="br0">(</span> conditionB <span class="br0">)</span> <span class="br0">{</span>
statement<span class="sy0">-</span>listB<span class="sy0">;</span>
<span class="br0">}</span>
...
<span class="kw1">else</span> <span class="br0">{</span>
statement<span class="sy0">-</span>listN<span class="sy0">;</span>
<span class="br0">}</span></pre>
<p>
The if construct is a branching mechanism that allows different code to execute
under different conditions. The conditions are evaluated in order, and the
statement-list of the first condition to evaluate to true is executed. If no
conditions evaluate to true and an else statement is present, then the
statement list within the else block will be executed. All of the else blocks
are optional.
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Related Topics: <a href="../keywords/else.html" class="wikilink1" title="keywords:else">else</a>, <a href="../keywords/for.html" class="wikilink1" title="keywords:for">for</a>, <a href="../keywords/switch.html" class="wikilink1" title="keywords:switch">switch</a>, <a href="../keywords/while.html" class="wikilink1" title="keywords:while">while</a>
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