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Python Python Basics (2015) Python Data Types Deletion

Challenge 2 of 2: "And, finally, we need to remove that 2. Can you delete it with del, too? Thanks!"

I know this can be solved with

messy = [5, 2, 8, 1, 3]
del messy[2]
del messy[1]

But the code challenge won't accept an index value of -4 as correct also:

messy = [5, 2, 8, 1, 3]
del messy[2]
del messy[-4]

I ran this in my terminal and it worked...thinking it's just a glitch in Workspaces. But just in case I'm wrong I wanted to point it out...am I missing something?

1 Answer

Chris Freeman
MOD
Chris Freeman
Treehouse Moderator 68,454 Points

Keep in mind that after the first del the indexes of the list items shift. The two solutions produce different results:

# Your first example
>>> messy = [5, 2, 8, 1, 3]
>>> del messy[2]
>>> messy
[5, 2, 1, 3]
>>> del messy[1]
>>> messy
[5, 1, 3]

# Your Second example
>>> messy = [5, 2, 8, 1, 3]
>>> del messy[2]
>>> messy
[5, 2, 1, 3]
>>> del messy[-4]
>>> messy
[2, 1, 3]