class Solution

 {

 public:

     int GetLastIndex(char c,string str)

     {

         for(int i = str.length() - ; i >= ; i --)

         {

             if(str[i] == c)

             {

                 return i;

             }

         }

         return -;

     }

     int FirstNotRepeatingChar(string str)

     {

         if(str == "")    return -;

         int id = -;

         bool judge[str.length()];

         for(int i = ; i < str.length(); i ++)

             judge[i] = false;

         for(int i = ; i < str.length(); i ++)

         {

             id = GetLastIndex(str[i],str);

             if(id == i && !judge[i])

                 return i;

             judge[i] = judge[id] = true;

         }

         return -;

     }

 };