I am getting a name error in a simple calculator program.

Question

to run the code you enter 2 number and the first letter of one of 4 operations. a=+, s=-,m =*,d=/
https://code.sololearn.com/cbLVF8kdRQ50/?ref=app

Answer 1

The NameError is because a, s, m, and d are interpreted as variables, instead of values. To make them string values, surround them in either single quotes or double quotes. Then you can compare them to the input.
Ex:
if op == "a":

Answer 2

thanks that makes sence