#Program to make a simple calculator

#This function adds two numbers

def add (x, y):

return x + y

#This function subtracts two numbers

def subtract (x, y):

return x - y

#This function multiplies two numbers

def multiply (x, y):

return x * y

#This function divides two numbers

def divide (x, y):

return x / y

print ("Select operation.")

print ("1.Add")

print ("2.Subtract")

print ("3.Multiply")

print ("4.Divide")

while True:

#Take input from the user

choice = input ("Enter choice(1/2/3/4): ")

#Check if the choice is one of the four options

if choice in ('1', '2', '3', '4'):

    num1 = float (input("Enter first number: "))

    num2 = float (input("Enter second number: "))

    if choice == '1':

        print (num1, "+", num2, "=", add(num1, num2))

    elif choice == '2':

        print (num1, "-", num2, "=", subtract(num1, num2))

    elif choice == '3':

        print(num1, "*", num2, "=", multiply(num1, num2))

    elif choice == '4':
        print (num1, "/", num2, "=", divide(num1, num2))
    break

else:
    print ("Invalid Input")