# Program to demonstrate Nested If and Elif approach
# Ian Ford - 2019-09-25

# function to show how nested ifs work
def useNestIf():
    print("Using Nested IFs")
    cont = "" #  variable to allow multiple inputs

    while cont != "X":

        theScore = int(input("Exam score (X to finish): "))

        if theScore > 80:
            print("Grade A")
        else:
            if theScore > 70:
                print("Grade B")
            else:
                if theScore > 60:
                    print("Grade C")
                else:
                    print("You failed")

        print()
        cont = input("Continue? (X to stop): ").upper()
        print()
# end of useNestIF() function

# function to show how elif work
def useElseIf():
    print("Using ELIF")
    cont = "" # variable to allow multiple inputs

    while cont != "X":

        theScore = int(input("Exam score (X to finish): "))

        if theScore > 80:
            print("Grade A")
        elif theScore > 70:
            print("Grade B")
        elif theScore > 60:
            print("Grade C")
        else:
            print("You failed")

        print()
        cont = input("Continue? (X to stop): ").upper()
        print()
# end of useElseIf() function    

# MAIN PROGRAM

print("Exam score program using elif and Nested If")
print()

option = ""

while option != "X":
    print("""Choose a method

Enter 1 to use Nested Ifs
Enter 2 to use ELIF
Enter X to exit
""")
    option = input("Enter your choice: ").upper()
    print()

    if option == "1":
        useNestIf() #call the function
    elif option == "2":
        useElseIf() #call the function
    #note: no else statement here