Problem 45239. Checkmate-02

It shows all kids that just because a code works does not mean it is correct. It is possible to create all kinds of code, even the ones that reproduce the wrong answers someone made. If you have a board at home, set up test number 10 and check the valid positions.

And that's the problem with using code to verify code (For people dreaming of complete automation), we can only guarantee that our code has the same errors as the original code, not that the original code is correct.