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    copied!<p>The definition of map is:<br> <b>map&lt;Key, Data, Compare, Alloc&gt;</b></p> <p>Where the last two template parameters default too:<br> Compare:&nbsp;less&lt;Key&gt;<br> Alloc:&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;allocator&lt;value_type&gt;<br></p> <p>When inserting new values into a map. The new value (valueToInsert) is compared against the old values in order (<b>N.B.</b> This is not sequential search, the standard guarantees a max insert complexity of O(log(N)) ) until Compare(value,ValueToInsert) returns true. Because you are using <b><i>'const char*'</i></b> as the key. The Compare Object is using <b><i>less&lt;const char*&gt;</i></b> this class just does a &lt; on the two values. So in effect you are comparing the pointer values (not the string) therefore the order is random (as you don't know where the compiler will put strings.</p> <p>There are two possible solutions:</p> <ul> <li>Change the type of the key so that it compares the string values.</li> <li>Define another Compare Type that does what you need.</li> </ul> <p>Personally I (like Chris) would just use a std::string because &lt; operator used on strings returns a comparison based on the string content. But for arguments sake we can just define a Compare type.</p> <pre><code>struct StringLess { bool operator()(const char* const&amp; left,const char* const&amp; right) const { return strcmp(left,right) &lt; 0; } }; /// typedef std::map&lt;const char*, int,StringLess&gt; TMyMap; </code></pre>
 

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