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.
First part is quite obvious. The second one uses RegExp /rp|ps|sr/ to test concatenated string from first characters of A and B. It's pretty simple. Just read about regexp on MDN.
I know it's 4 months too late, but for you or anyone else whos interested, there's a good tutorial here: https://www.w3schools.com/python/python_lambda.asp