I solved D-Lakes in Berland(Round #375 Div2) in the contest and I got Accepted,
Link : http://mirror.codeforces.com/contest/723/problem/D
My submission : http://mirror.codeforces.com/contest/723/submission/21161297
However after the contest I found a counter test that my code gets wrong , here it is :
the output should be 2304 (changes) instead the output is 0 ,
the problem is that I was looping from 1 to 500 instead of 2500 .
is the test right ? is there a bug in the system test ?
By Width
I think the system tests are weak because my code gives
2304for the given test and it also got accepted during contest. So, the test case is right but the system tests are weak. They are more focused on the cases where some lakes are connected to the sea. ~~~~~ You can write to the author so that they can update it for practice. ~~~~~I already wrote to them