num1 = float(input("Erste Zahl: "))
operator = input("Enter Operator(+, -, *, /): ")
num2 = float(input("Zweite Zahl: "))

if operator == "+":
    result = num1 + num2
elif operator == "-":
    result = num1 - num2
elif operator == "*":
    result = num1 * num2
elif operator == "/":
    result = num1 / num2
else:
    print("Ungültiger Operator.")
    result = None 

if result is not None:
    print(f"Das Ergebnis ist: {result}")