This is A C++ program question:

Please use Loop Algorithms and you may not use stdafx.h.

Consider only for loop and while loop.

Write a program that reads a string and prints the most frequently occurring letter. If there are multiple letters that occur with the same maximum frequency, print them all. For example, if the word is mississippi, print is because i and s occur four times each, and no letter occurs more frequently.

You do not to worry about upper case

The maximum number of letters that tie for most frequent is three times and at least one repeated letter