int toupper(int ch);
            int tolower(int ch);
         

Example:

            char s[] = "hello";
            s[0] = toupper(s[0]);

            cout << s << endl;

            Output: Hello
         

            char s[100000];

            memset(s, 'X', 100000);

         

This sets all elements to be 'X' and is much faster than writing a loop (maybe 15 to 20 times as fast for arrays this size.).