For Java :

Ask the user if they are taking a class (enter yes or no). If they are not taking a class print "Thanks for using the system." and close the program. If they are taking a class proceed to ask for a grade as listed below. If the input is not "yes" or "no" print "Invalid input" and close. This should work regardless of capital or lowercase inputs. Use if/else if/else for this part. If and only if the user is taking a class, ask them to enter a letter grade (A, B, C, D, or F, uppercase or lowercase). If they enter A or B, print "Great Job!" If they enter C print "You're doing alright." If they enter D or F print "You can improve." If they enter anything else then print "Invalid grade." Regardless of input then close (including invalid). Use a switch statement for this portion