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    copied!<p>I do agree that <code>std::map&lt;string, string&gt;</code> will have advantages over <code>std::map&lt;char*, char*&gt;</code>. Specially having the key as value rather than pointer would provide the expected search/find results.</p> <p>But, sometimes we do need pointer in map definition specially in the value part when map’s value part is heavy object of a user defined class. By heavy object , I mean copy constructor of the class does a significant amount of work. In such scenarios, value part of the map should be a pointer. Using a raw pointer would leak the memory as mentioned above. Smart pointer would be a better choice ensuring no memory is leaked.</p> <p>Sample example: Consider the below class</p> <pre><code>class ABCD { public: ABCD(const int ab) : a(ab) {cout &lt;&lt; "Constructing ABC object with value : " &lt;&lt; a &lt;&lt; endl;} ~ABCD() {cout &lt;&lt; "Destructing ABC object with value : "&lt;&lt; a &lt;&lt; endl;} void Print() { cout &lt;&lt; "Value is : " &lt;&lt; a &lt;&lt; endl;} private: int a; }; </code></pre> <p>Consider the code where-in smart pointer of the above class is used:</p> <pre><code>{ std::map&lt;_tstring, std::shared_ptr&lt;ABCD&gt;&gt; myMap; _tstring key(_T("Key1")); myMap.insert(std::make_pair(key, std::make_shared&lt;ABCD&gt;(10))); auto itr = myMap.find(key); itr-&gt;second-&gt;Print(); myMap[key] = std::make_shared&lt;ABCD&gt;(20); itr = myMap.find(key); itr-&gt;second-&gt;Print(); } // myMap object is destroyed, which also calls the destructor of ABCD class </code></pre> <p>Output from above code is:</p> <pre><code>Constructing ABC object with value : 10 Value is : 10 Constructing ABC object with value : 20 Destructing ABC object with value : 10 Value is : 20 Destructing ABC object with value : 20 </code></pre>
 

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