In C program Given a string of both uppercase and lowercase letters, print the most frequent letter or letters in the string in uppercase. Consider both letters in uppercase and lowercase as a single...

In C program

Given a string of both uppercase and lowercase letters, print the most frequent letter or letters in the string in uppercase. Consider both letters in uppercase and lowercase as a single letter (i.e. the count of 'a' and 'A' is combined and treated the same).

Input

A string of varied length composed of uppercase and lowercase letters and spaces.

A sample string
Output

The most frequent letter/s in the input. If there are more than one letter, print them alphabetically in new lines.

A
S