int d[27]={0}; for (int i = 0; i < str.length(); i++) //AABBCC d[str[i] - 'A']++; for (int i = 0; i < str.length(); i++) if (d[str[i] - 'A'] != 0) { cout << str[i] << " "<< d[str[i] - 'A'] << " "; //A 2 B 2 C 2 }