1 class Solution { 2 public: 3     char findTheDifference(string s, string t) { 4         map<char,int>Map_Temp; 5         for(int i=0;i<s.size();i++) 6         Map_Temp[s[i]-‘a‘]++; 7         for(int i=0;i<t.size();i++) 8         Map_Temp[t[i]-‘a‘]--; 9         map<char,int>::iterator iter;10         for(iter=Map_Temp.begin();iter!=Map_Temp.end();iter++)11         if(iter->second)12         return char(iter->first+‘a‘);13         return 0;14     }15 };