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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.
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Adds a letter to the arrays from the 'abc' array depending on the index 'a', which is perfectly manipulated by the author, subtracting and adding at the right moments.