The statement of the problem says: "Output the value of the convergent continued fraction of order k of the square root of x as an IRREDUCIBLE fraction."
But it is well-known, that every such convergent fraction is irreducible. However after taking modulo it may become reducible. So I thought I should reduce the answer in this case. But it is not true! You don't have to do it. Otherwise you'll get WA#8.

May admins clarify this misunderstanding somehow, please?