Loading collection data...
Collections are a way for you to organize kata so that you can create your own training routines. Every collection you create is public and automatically sharable with other warriors. After you have added a few kata to a collection you and others can train on the kata contained within the collection.
Get started now by creating a new collection.
I reread it, and I suppose that you did say "n lockers and n runs" but you did that inside the text box.
When you described how many times he runs by, and what he does when he runs by, you get to 3 and then stop. That description makes me (as well as others, obviously) think that he only runs three times.
Maybe just add something that explaings outside of the text box that states that he runs once for each locker there is.
total lockers : 5
open after second run : [1, 3, 5]
lockers affected by second run : [3]
returned [1, 5] should equal [1, 4]
How is it possible that 4 should be open but 5 should be closed?
Am I missing something?
This comment is hidden because it contains spoiler information about the solution