# store all possible operators
operators = ["+","-","*","/","**","//"]

validNumber = False
while not validNumber:
    try:
        num1 = float(input("enter the first number : "))
        validNumber = True
    except ValueError:
        print("invalid number")


validOperator = False
while not validOperator:
    try:
        operator = input("enter the operator \n(+ or - or * or / or ** = Power or // ) : ")
        if operator in operators:
            validOperator = True
        else:
            print("invalid operator")
    except ValueError:
        print("invalid operator")

validNumber = False
while not validNumber:
    try:
        num2 = float(input("enter the second number : "))
        validNumber = True
    except ValueError:
        print("invalid number")

print()

if operator == "+":
    print(f"{int(num1)} + {int(num2)} = {num1+num2}")
elif operator == "-":
    print(f"{int(num1)} {int(num2)} = {num1-num2}")
elif operator == "*":
    print(f"{int(num1)} x {int(num2)} = {num1*num2}")
elif operator == "x":
    print(f"{int(num1)} x {int(num2)} = {num1*num2}")
elif operator == "/":
    print(f"{int(num1)} / {int(num2)} = {num1/num2}")
elif operator == "+":
    print(f"{int(num1)} + {int(num2)} = {num1/num2}")
elif operator == "**":
    print(f"{int(num1)} ** {int(num2)} = {num1**num2}")
elif operator == "//":
    print(f"{int(num1)} // {int(num2)} = {num1//num2}")
else:
    print("you used invalid operator.")