Vrijeme: 11:07

Ploče! | Boards! #1

Želimo postaviti m polukraljica na šahovsku ploču dimenzija 1001 \times 1001; one mogu napadati vodoravno, okomito ili po dijagonali prema dolje-desno/gore-lijevo (tj. u šest smjerova), a napadaju i polje na kojem se nalaze. Odredite najmanji m takav da postoji raspored u kojem je svako polje na ploči napadnuto barem jednom polukraljicom.

We want to place m semi-queens on a 1001 \times 1001 chessboard. A semi-queen can attack horizontally, vertically, and along the downward-right / upward-left diagonals (i.e., in six directions), and it also attacks the square it occupies. Determine the minimum m such that there exists an arrangement in which every square on the board is attacked by at least one semi-queen.