Why am I getting an error?

Question

I’m trying to make a simple calculator. In the last line, I get an error saying “result” is not defined. How do I fix this?

while True:
print("type 'add' to add two numbers")
print("type 'subtract' to subtract two numbers")
print("type 'divide' to divide two numbers")
print("type 'multiply' to multiply two numbers")
print("type 'quit' to end program")
user_input=input("operation:")
print(user_input)
if user_input==("quit"):
break

num1=float(input("number 1:"))
print(num1)
num2=float(input("number 2:"))
print(num2)

if input==("add"):
result=str(num1+num2)

elif input==("subtract"):
result=str(num1-num2)

elif input==("multiply"):
result=str(num1*num2)

elif input==("divide"):
result=str(num1/num2)

print("answer:"+result)

Answer 1

You named the operation input user_input but in the if-elif-part you write input. And there is no need to put "add" and so on in a tuple, right?

Answer 2

In the if statements you write "if/elif input==("operation") , but "input" doesn't exist only exist "user_input", change this, and is unnecessary write the parentheses