static long CoordToHash(int r, int c) {
            return r + ((long) c << 32);
        }

        static int WalkPath(int rq, int cq, int dr, int dc, int n, HashSet<long> obstacles) {
            int result = 0;
            rq += dr;
            cq += dc;
            while (rq != 0 && cq != 0 && rq != n + 1 && cq != n + 1) {
                if (obstacles.Contains(CoordToHash(rq, cq)))
                    break;
                rq += dr;
                cq += dc;
                result++;
            }
            return result;
        }

        static int queensAttack(int n, int k, int rQ, int cQ, int[][] obstacles) {
            HashSet<long> obstaclesSet = new HashSet<long>();
            foreach (int[] obstacle in obstacles) {
                obstaclesSet.Add(CoordToHash(obstacle[0], obstacle[1]));
            }
            return WalkPath(rQ, cQ, -1, -1, n, obstaclesSet) +
                   WalkPath(rQ, cQ, -1, 0, n, obstaclesSet) +
                   WalkPath(rQ, cQ, -1, 1, n, obstaclesSet) +
                   WalkPath(rQ, cQ, 0, 1, n, obstaclesSet) +
                   WalkPath(rQ, cQ, 1, 1, n, obstaclesSet) +
                   WalkPath(rQ, cQ, 1, 0, n, obstaclesSet) +
                   WalkPath(rQ, cQ, 1, -1, n, obstaclesSet) +
                   WalkPath(rQ, cQ, 0, -1, n, obstaclesSet);
        }