public static int blocked(int x, int y, char d)
    {
        switch (d)
        {
            case 'N':
                Triple pN = new Triple(x, y, 'N');
                Triple pS = new Triple(x, y + 1, 'S');
                if (blocks.containsKey(pN) || blocks.containsKey(pS))
                    return 0;
                return 1;

            case 'E':
                Triple pE = new Triple(x, y, 'E');
                Triple pW = new Triple(x + 1, y, 'W');
                if (blocks.containsKey(pE) || blocks.containsKey(pW))
                    return 0;
                return 1;
        }
        return 1;
    }