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insert [C++ Reference]
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<h2><a name="insert" id="insert">insert</a></h2>
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<p>
Syntax:
</p>
<pre class="c code c++" style="font-family:monospace;"> <span class="co2">#include <set></span>
pair<span class="sy0"><</span>iterator<span class="sy0">,</span> bool<span class="sy0">></span> set<span class="sy0">::</span><span class="me2">insert</span><span class="br0">(</span><span class="kw4">const</span> TYPE<span class="sy0">&</span> val<span class="br0">)</span><span class="sy0">;</span>
iterator set<span class="sy0">::</span><span class="me2">insert</span><span class="br0">(</span>iterator pos<span class="sy0">,</span> <span class="kw4">const</span> TYPE<span class="sy0">&</span> val<span class="br0">)</span><span class="sy0">;</span>
<span class="kw4">void</span> set<span class="sy0">::</span><span class="me2">insert</span><span class="br0">(</span>input_iterator start<span class="sy0">,</span> input_iterator end<span class="br0">)</span><span class="sy0">;</span></pre>
<p>
The method insert() either:
</p>
<ul>
<li class="level1"><div class="li"> inserts val, but only if val doesn't already exist. The return value is an iterator to the element inserted, and a boolean describing whether an insertion took place. If bool is false, the iterator points to where the element already was.</div>
</li>
<li class="level1"><div class="li"> inserts val before the element at pos (where pos is really just a suggestion as to where val should go, since sets and maps are ordered), and returns an iterator to that element.</div>
</li>
<li class="level1"><div class="li"> inserts a range of elements from start to end.</div>
</li>
</ul>
<p>
For example, the following code uses insert to populate a set of integers:
</p>
<pre class="c code c++" style="font-family:monospace;"> <span class="kw4">const</span> <span class="kw4">int</span> max_nums <span class="sy0">=</span> <span class="nu0">10</span><span class="sy0">;</span>
<span class="kw4">int</span> nums<span class="br0">[</span>max_nums<span class="br0">]</span> <span class="sy0">=</span> <span class="br0">{</span>3<span class="sy0">,</span>1<span class="sy0">,</span>4<span class="sy0">,</span>1<span class="sy0">,</span>5<span class="sy0">,</span>9<span class="sy0">,</span>2<span class="sy0">,</span>6<span class="sy0">,</span>5<span class="sy0">,</span>8<span class="br0">}</span><span class="sy0">;</span>
set<span class="sy0"><</span>int<span class="sy0">></span> digits<span class="sy0">;</span>
<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> max_nums<span class="sy0">;</span> <span class="sy0">++</span>i <span class="br0">)</span> digits.<span class="me1">insert</span><span class="br0">(</span>nums<span class="br0">[</span>i<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> <span class="st0">"Unique digits are: "</span><span class="sy0">;</span>
<span class="kw1">for</span><span class="br0">(</span> set<span class="sy0"><</span>int<span class="sy0">>::</span><span class="me2">const_iterator</span> iter <span class="sy0">=</span> digits.<span class="me1">begin</span><span class="br0">(</span><span class="br0">)</span><span class="sy0">;</span>
iter <span class="sy0">!=</span> digits.<span class="me1">end</span><span class="br0">(</span><span class="br0">)</span><span class="sy0">;</span>
<span class="sy0">++</span>iter <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="sy0">*</span>iter <span class="sy0"><<</span> <span class="st0">' '</span><span class="sy0">;</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">'<span class="es1">\n</span>'</span><span class="sy0">;</span></pre>
<p>
When run, this code displays:
</p>
<pre class="code">
Unique digits are: 1 2 3 4 5 6 8 9</pre>
<p>
Related Topics: <a href="../../stl/set/begin.html" class="wikilink1" title="stl:set:begin">begin</a>, <a href="../../stl/set/end.html" class="wikilink1" title="stl:set:end">end</a>
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