"NameError" when supplying variable name to input() prompt

Question

I have this simple bit of code I can't get to work any advice?

a = 2
b = 4
c = input()
d = 0
d = c + 5
print(d)

Say I input a, so 2, I should get 7. But I don't. This Python 3. Using Wing IDE 101 (ver. 5) here. I get this as my error output.

Traceback (most recent call last): File "", line 1, in builtins.NameError: name 'a' is not defined

Answer 1

Are you sure you are using Python 3? In python 2.x you can do it by explictly evaluating an string expression with the eval() function:

 c = eval(raw_input()) # Python 2.7
 c = eval(input()) # Python 3.x

In Python 3.x input() will convert the input in a string and won't raise that error (NameError). It will raise a TypeError instead, because you cannot concatenate str and int that way.

Answer 2

you can just try c = raw_input()