OKEA（CF）

You work for a well-known department store that uses leading technologies and employs mechanistic work — that is, robots!
The department you work in sells n⋅kn⋅k items. The first item costs 11 dollar, the second item costs 22 dollars, and so on: ii-th item costs ii dollars. The items are situated on shelves. The items form a rectangular grid: there are nn shelves in total, and each shelf contains exactly kk items. We will denote by ai,jai,j the price of jj-th item (counting

OKEA（CF）最先出现在Python成神之路。