# menu driven calculator.

while True:
    num1 = int(input("Enter the first number: "))
    num2 = int(input("Enter the second number: "))

    op = input("Enter the operation you want to perform: + - * / // % ")

    def addition(num1, num2):
        return num1 + num2

    def subtraction(num1, num2):
        return num1 - num2

    def multiplication(num1, num2):
        return num1 * num2

    def division(num1, num2):
        if num2 == 0:
            return "Error! Division by zero"
        else:
            return num1 / num2

    def floor_division(num1, num2):
        if num2 == 0:
            return "Error! Division by zero"
        else:
            return num1 // num2

    def modulus(num1, num2):
        if num2 == 0:
            return "Error! Division by zero"
        else:
            return num1 % num2

    if op in ('+', '-', '*', '/', '//', '%'):
        if op == '+':
            print("Result:", addition(num1, num2))
        elif op == '-':
            print("Result:", subtraction(num1, num2))
        elif op == '*':
            print("Result:", multiplication(num1, num2))
        elif op == '/':
            print("Result:", division(num1, num2))
        elif op == '//':
            print("Result:", floor_division(num1, num2))
        elif op == '%':
            print("Result:", modulus(num1, num2))
    else:
        print("Invalid operation. Please enter one of the following: + - * / // %")

    choice = input("Press Y to continue or any key to terminate: ")
    if choice.upper() != 'Y':
        break