Question

Here is an example of what I mean:

a = 0
b = 1

c = range(3)

so I would like to find the missing number in the list which in this case would be 2.

The way I have programmed it at the moment is cumbersome and ugly.

If there was a function opposite to list.append() so that I could remove values from the list instead that would be great to.

Thanks

Answer 1

Use set difference by converting the list to a set, then preforming the set difference operation.

>>> supplied_list = [0, 1]
>>> list(set(range(3)) - set(supplied_list))
[2]