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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.
Mention the language you used when reporting a problem, please.
Why do you want to use &&, if all conditions are necessary (or better said: if any of those conditions are true we must return -1)?