def calculate(firstOperand, secondOperand, operand):
        if operand == '+':
                print(int(firstOperand) + int(secondOperand))
        elif operand == '-':
                print(int(firstOperand) - int(secondOperand))
        elif operand == '*':
                print(int(firstOperand) * int(secondOperand))
        elif operand == '/':
                print(int(firstOperand)  / int(secondOperand))
        else:
                print("Invalid input. Try again\n")
                menu()

def menu():
        print("\nWelcome to the calculator program")
        print("Please enter your operands and  operator")
        firstOperand = raw_input("\nFirst operand:")
        secondOperand = raw_input("\nSecond operand:")
        operand = raw_input("\n Operand:")
        return (firstOperand, secondOperand, operand)

(firstOperand, secondOperand, operand) = menu()

calculate(firstOperand, secondOperand, operand)