problem no 58:(problem on string):Non Repeating Character .

 QUESTION:

Given a string S consisting of lowercase Latin Letters. Find the first non-repeating character in S.

Example 1:

Input:
S = hello
Output: h
Explanation: In the given string, the
first character which is non-repeating
is h, as it appears first and there is
no other 'h' in the string.

Example 2:

Input:
S = zxvczbtxyzvy
Output: c
Explanation: In the given string, 'c' is
the character which is non-repeating.  

ANSWER: 

 char nonrepeatingCharacter(string s)
    {
       map<char ,int> m;
       for(int i=0;i<s.size();i++)
       {
           m[s[i]]++;
       }
       
       int foundwithsingleexistence=0;
       for(int i=0;i<s.size();i++)
       {
           char a=s[i];
           int num=m[a];
           if(num==1)
           {
               foundwithsingleexistence=1;
               return a;
           }
       }
       if(foundwithsingleexistence==0)
       {
           return '$';  
       }
     
    }