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.
Maybe try regular expressions, they are quite powerful but not that easy to get the actual pattern right
It's a 3 kyu, it's intended to be difficult.
The task might be easier than you think, and building a parser for arithmetic expressions is not that difficult. But not trivial either :)