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generate_n [C++ Reference]
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<h2><a name="generate_n" id="generate_n">generate_n</a></h2>
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<p>
Syntax:
</p>
<pre class="c code c++" style="font-family:monospace;"> <span class="co2">#include <algorithm></span>
<span class="kw4">void</span> generate_n<span class="br0">(</span> output_iterator result<span class="sy0">,</span> SIZE num<span class="sy0">,</span> Generator g <span class="br0">)</span><span class="sy0">;</span></pre>
<p>
The generate_n() function runs the Generator function object g num times,
saving the result of each execution in result, (result+1), etc.
</p>
<p>
For example, the following code uses generate_n() to fill an array of int with random numbers using the standard C library rand function:
</p>
<pre class="c code c++" style="font-family:monospace;"> <span class="co2">#include <cstddef></span>
<span class="co2">#include <cstdlib></span>
<span class="co2">#include <iostream></span>
<span class="co2">#include <iterator></span>
<span class="co2">#include <algorithm></span>
<span class="kw4">int</span> main<span class="br0">(</span><span class="br0">)</span>
<span class="br0">{</span>
<span class="kw4">const</span> std<span class="sy0">::</span><span class="me2">size_t</span> N <span class="sy0">=</span> <span class="nu0">5</span><span class="sy0">;</span>
<span class="kw4">int</span> ar<span class="br0">[</span>N<span class="br0">]</span><span class="sy0">;</span>
std<span class="sy0">::</span><span class="me2">generate_n</span><span class="br0">(</span>ar<span class="sy0">,</span> N<span class="sy0">,</span> std<span class="sy0">::</span><span class="me2">rand</span><span class="br0">)</span><span class="sy0">;</span> <span class="co1">// Using the C function rand()</span>
std<span class="sy0">::</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">"ar: "</span><span class="sy0">;</span>
std<span class="sy0">::</span><span class="me2">copy</span><span class="br0">(</span>ar<span class="sy0">,</span> ar<span class="sy0">+</span>N<span class="sy0">,</span> std<span class="sy0">::</span><span class="me2">ostream_iterator</span><span class="sy0"><</span>int<span class="sy0">></span><span class="br0">(</span>std<span class="sy0">::</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">" "</span><span class="br0">)</span><span class="br0">)</span><span class="sy0">;</span>
<a href="http://www.opengroup.org/onlinepubs/009695399/functions/cout.html"><span class="kw3">cout</span></a> <span class="sy0"><<</span> endl<span class="sy0">;</span>
<span class="br0">}</span></pre>
<p>
Related Topics: <a href="../../stl/algorithm/generate.html" class="wikilink1" title="stl:algorithm:generate">generate</a>
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