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    copied!<p>I understand your question that you want map: <code>key-&gt;map&lt;key,&gt;::iterator</code></p> <p>So, here it is, a struct with map iterator as value:</p> <pre><code>template &lt; template &lt;class K, class V, class C, class A&gt; class mapImpl, class K, class V, class C=std::less&lt;K&gt;, class A=std::allocator&lt;std::pair&lt;const K, V&gt; &gt; &gt; class value_with_iterator { public: typedef typename mapImpl&lt;const K,value_with_iterator,C,A&gt;::iterator value_type; value_type value; }; </code></pre> <p>Map defined with using struct above: </p> <pre><code>typedef std::map&lt;size_t, value_with_iterator &lt;std::map, size_t, size_t&gt; &gt; map_size_t_to_itself; </code></pre> <p>Some insert method - to link key with itself:</p> <pre><code>map_size_t_to_itself::iterator insert(map_size_t_to_itself&amp; mapRef, size_t value) { map_size_t_to_itself::value_type v(value, map_size_t_to_itself::mapped_type()); std::pair&lt;map_size_t_to_itself::iterator, bool&gt; res = mapRef.insert(v); if (res.second) res.first-&gt;second.value = res.first; return res.first; } </code></pre> <p>And simple test:</p> <pre><code>int main() { map_size_t_to_itself mapObj; map_size_t_to_itself::iterator i1 = insert(mapObj, 1); map_size_t_to_itself::iterator i2 = insert(mapObj, 1); map_size_t_to_itself::iterator i3 = insert(mapObj, 2); std::cout &lt;&lt; i1-&gt;first &lt;&lt; ": " &lt;&lt; i1-&gt;second.value-&gt;first &lt;&lt; std::endl; std::cout &lt;&lt; i2-&gt;first &lt;&lt; ": " &lt;&lt; i2-&gt;second.value-&gt;first &lt;&lt; std::endl; std::cout &lt;&lt; i3-&gt;first &lt;&lt; ": " &lt;&lt; i3-&gt;second.value-&gt;first &lt;&lt; std::endl; } </code></pre> <p>with OUTPUT:</p> <pre><code>1: 1 1: 1 2: 2 </code></pre> <p>Full link: <a href="http://ideone.com/gnEhw" rel="noreferrer">http://ideone.com/gnEhw</a></p>
 

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