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.
to make it even shorter you could replace
sum = sum + num
with
sum += num
it show an error:
slice out of bound
this solution can be improved!
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