Counting letters: Use pointer arithmetic to write a program that reads a word and a

letter from the user and counts the number of times the letter occurred in the string. The

program should output the index position$($s$)$ where it found the letter, as well as print the

number of times it found it$.$ Example:

Enter a word: anna

Enter a letter: n

Letter found at index position$($s$)1,2$

Letter found $2$ times.