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<h2><a name="insert" id="insert">insert</a></h2>
<div class="level2">
<p>
Syntax:
</p>
<pre class="c code c++" style="font-family:monospace;"><span class="co2">#include <map></span>
iterator insert<span class="br0">(</span> iterator pos<span class="sy0">,</span> <span class="kw4">const</span> TYPE<span class="sy0">&</span> pair <span class="br0">)</span><span class="sy0">;</span>
<span class="kw4">void</span> insert<span class="br0">(</span> input_iterator start<span class="sy0">,</span> input_iterator end <span class="br0">)</span><span class="sy0">;</span>
pair<span class="sy0"><</span>iterator<span class="sy0">,</span>bool<span class="sy0">></span> insert<span class="br0">(</span> <span class="kw4">const</span> TYPE<span class="sy0">&</span> pair <span class="br0">)</span><span class="sy0">;</span></pre>
<p>
There are three versions of the <code>insert</code> method for maps:
</p>
<ol>
<li class="level1"><div class="li"> inserts <code>pair</code> after the element at <code>pos</code> (where <code>pos</code> is really just a suggestion as to where <code>pair</code> 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 <code>start</code> to <code>end</code>.</div>
</li>
<li class="level1"><div class="li"> inserts <code>pair<key,val></code>, but only if no element with key <code>key</code> already exists. The return value is an iterator to the element inserted (or an existing pair with key <code>key</code>), and a boolean which is true if an insertion took place.</div>
</li>
</ol>
<p>
For example, the following code uses insert function (along with <a href="../../stl/utility/make_pair.html" class="wikilink1" title="stl:utility:make_pair">make_pair</a>) to insert some data into a map, and then displays that data:
</p>
<pre class="c code c++" style="font-family:monospace;">map<span class="sy0"><</span>string<span class="sy0">,</span>int<span class="sy0">></span> theMap<span class="sy0">;</span>
theMap.<span class="me1">insert</span><span class="br0">(</span> make_pair<span class="br0">(</span> <span class="st0">"Key 1"</span><span class="sy0">,</span> <span class="sy0">-</span>1 <span class="br0">)</span> <span class="br0">)</span><span class="sy0">;</span>
theMap.<span class="me1">insert</span><span class="br0">(</span> make_pair<span class="br0">(</span> <span class="st0">"Another key!"</span><span class="sy0">,</span> 32 <span class="br0">)</span> <span class="br0">)</span><span class="sy0">;</span>
theMap.<span class="me1">insert</span><span class="br0">(</span> make_pair<span class="br0">(</span> <span class="st0">"Key the Three"</span><span class="sy0">,</span> 66667 <span class="br0">)</span> <span class="br0">)</span><span class="sy0">;</span>
map<span class="sy0"><</span>string<span class="sy0">,</span>int<span class="sy0">>::</span><span class="me2">iterator</span> iter<span class="sy0">;</span>
<span class="kw1">for</span><span class="br0">(</span> iter <span class="sy0">=</span> theMap.<span class="me1">begin</span><span class="br0">(</span><span class="br0">)</span><span class="sy0">;</span> iter <span class="sy0">!=</span> theMap.<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="st0">"Key: '"</span> <span class="sy0"><<</span> iter<span class="sy0">-></span>first <span class="sy0"><<</span> <span class="st0">"', Value: "</span> <span class="sy0"><<</span> iter<span class="sy0">-></span>second <span class="sy0"><<</span> endl<span class="sy0">;</span>
<span class="br0">}</span></pre>
<p>
When run, the above code displays this output:
</p>
<pre class="code">
Key: 'Another key!', Value: 32
Key: 'Key 1', Value: -1
Key: 'Key the Three', Value: 66667</pre>
<p>
Note that because maps are sorted containers, the output is sorted by the key
value. In this case, since the map key data type is <a href="../../string/start.html" class="wikilink1" title="string:start">string</a>, the map is sorted
alphabetically by key.
</p>
<p>
Related Topics: <a href="../../stl/map/operator.html" class="wikilink1" title="stl:map:map_operators">[] operator</a>
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