I'm working on an 8085 program to read sentences typed in by a user and then count the number of occurrences of a specific letter requested by the user.

Program begins with a prompt for a sentence- user can end the sentence by either hitting the return key or typing a period. The program should then ask for a letter. It should then count the number of occurrences of that letter in the sentence and print it to the
screen. User may type either a small or a capital letter. In either of the two cases, occurrences of both the small and the capital letter should be printed.

How does one approach this?