pub const ADJACENT_WITH_CENTER: [(isize, isize); 9] = [(-1, -1), (0, -1), (1, -1), (-1, 0), (0, 0), (1, 0), (-1, 1), (0, 1), (1, 1)]; pub const ADJACENT_WITHOUT_CENTER: [(isize, isize); 8] = [(-1, -1), (0, -1), (1, -1), (-1, 0), (1, 0), (-1, 1), (0, 1), (1, 1)];