The paper is devoted to a problem inspired by the "Minesweeper" computer
game. It is shown that certain configurations of open cells guarantee the
existence and the uniqueness of solution. Mathematically the problem is reduced
to some spectral properties of discrete differential operators. It is shown how
the uniqueness can be used to create a new game which preserves the spirit of
"Minesweeper" but does not require a computer.Comment: We add consideration of tables based on the triangle tiling of the
plane. Its paper version encounters situations typical for the computer
"Minesweeper" gam