Hello,
There is an error in the constraints of Y in the problem statement of https://www.codechef.com/problems/B3
I believe it should be -2100000000 ≤ Y ≤ 2100000000. Also Y=0 does not appear in the tests. Thus, the constraint could be rewritten as 0 < |Y| ≤ 2100000000.
Thanks!