good point. I beefed up the test cases to prevent "cheating". ty

I am not very good with specific points in javascript, main idea is not to change any nodes. Just to use some locals variables.

Okay, I fixed the description and added tests for empty arrays.

I'm not sure it needs deleting; it's subtly different to the other kata (returning an array of arrays rather than one 1-d array), allowing for either a recursive solution or a small function to return each layer.
Pascal's Triangle is a nice algorithm and this is a cleanly constructed kata.

thanks, I fixed an error in description

thanks for reply... you're right. Try now... test are more accurate...

Missed that somehow. So will this one need to be deleted?