Johnny is a boy who likes to open and close lockers. He loves it so much that one day, when school was out, he snuck in just to play with the lockers.
Each locker can either be open or closed. If a locker is closed when Johnny gets to it, he opens it, and vice versa.
The lockers are numbered sequentially, starting at 1.
Starting at the first locker, Johnny runs down the row, opening each locker.
Then he runs all the way back to the beginning and runs down the row again, this time skipping to every other locker. (2,4,6, etc)
Then he runs all the way back and runs through again, this time skipping two lockers for every locker he opens or closes. (3,6,9, etc)
He continues this until he has finished running past the last locker (i.e. when the number of lockers he skips is greater than the number of lockers he has).
https://www.codewars.com/kata/slamming-lockers/train/javascript
这个题目长的7kyu