New difficult tests were added to the problem testset. Previously accepted solutions were rejudged. None of them resisted. However, the fact that the problem is NP-complete doesn't mean that it is impossible to write a solution which passes only a few dozen of tests. Thanks to Maxim Buzdalov for making this set of tests.

I think you should set a new problem called Ship. Version 3, it's not fair to those people who already got AC, especially some guys like me who want to keep (Problems solved = Problems submitted).

I think two versions are more than enough))
And I don't like such NP problems, because for every solution there exist bad test cases. I think they mustn't be present in such problem sets at all.
By the way, does the author's solution pass new tests?