Board.Board.dfs C# (CSharp) Method

        private void dfs(int[] map, int x, int y)
        {
            if (!(((0 <= x) && (x < 32)) && ((0 <= y) && (y < 32))))
                return;

            int idx = y * 32 + x;
            if (map[idx] < 2)
                return;

            map[idx] = 0;
            dfs(map, x, y - 1);
            dfs(map, x - 1, y);
            dfs(map, x + 1, y);
            dfs(map, x, y + 1);
        }