This comment is hidden because it contains spoiler information about the solution
The method you're trying to use is not available in the Node version currently supported by CW.
1)it is not valid after anter69 made the change
2)the solution whose link you've replied is valid.
the first link posted below is still valid (see FArekkusu message)
Greatly enjoyed solving this. Thanks for making it!
But I do want to bemoan the choice to have the zero tile in the bottom right rather than the top left, haha.
Added a test case to all current languages to prevent this:
[[6,7,8], [0,1,2], [3,4,5]] --> False
same with this one
An incorrect solution may pass the tests.
Oops, forgot to port that over.
Ruby translation kumited, including random tests that expect true in 20% of the cases. Please check and approve