Why bhaiya has made n and k also of long long int type?

#1

i dont think, they should be of this type. they can be of int also,
and he has also made the books array to be of long long int. it can also be of int type.
only mid, ans, curr_pages, total_pages should be of long long according to me.

#2

hey @sirraghavgupta, if constraints are not high then you can it as int. Even if you take long long it will also work fine.