Why is this wrong?

def add(x, y):
    """This function adds two numbers"""

    return x + y


def subtract(x, y):
    """This function subtracts two numbers"""

    return x - y


def divide(x, y):
    """This function divides two numbers"""

    return x / y


def multiply(x, y):
    """This function multiplies two numbers"""

    return x * y


print("Select Operation:")
print("1.Addition")
print("2.Subtraction")
print("3.Multiplication")
print("4.Division")

choice = input("Enter operators 1,2,3 or 4")

num1 = float(input("Enter your first number:"))
num2 = float(input("Enter your 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, "x", num2, "=",  multiply(num1, num2))

elif choice == '4':
    print(num1, "÷", num2, "=",  divide(num1, num2))
else:
    print("Invalid input")