{AESC USU} UdH-WiNGeR's and XYZ's heuristics-based solutions failed to pass the tests.

Now the following programmers have AC:
- Dmitry 'Diman_YES' Kovalioff
- Ilya Grebnov[Ivanovo SPU]
- Kit

But {AESC USU} UdH-WiNGeR's solution seems to be rather good, so after some further optimization it may fit the TL and get AC. Good luck!