Program should still ask the user to input a grade (integer from 1-100) and then output the letter grade.  Scale:  Greater than 90 is an "A"; Greater than 80 to 90 is a "B", Greater than 70 to 80 is a "C", Greater than 60 to 70 is a "D", and 60 or less is an "F"

Program should have :

a.       A while loop so one does not have to re-start the program with every new grade

b.      Use any score less than 0 (zero) as the sentinel to stop the while loop.

c.       You need to use If and else statements, not just If statements.

d.      Input grade and letter grade should be output to screen with each number grade input.

e.      Finally, your application will calculate and output the average grade for students input.