机器人的运动范围

这题目虽然代码有点长，但是思路非常清晰，所以不难

class Solution {
    public int movingCount(int threshold, int rows, int cols) {
        if (rows == 0 || cols == 0)
            return 0;
        Queue<pair> queue = new LinkedList<>();
        queue.offer(new pair(0, 0));
        int res = 0, x = 0, y = 0;
        int[] dx = {-1, 0, 1, 0}, dy = {0, 1, 0, -1};
        boolean[][] st = new boolean[rows][cols];
        while (!queue.isEmpty()) {
            pair p = queue.poll();
            if (p.getS(p.row) + p.getS(p.col) > threshold || st[p.row][p.col] == true)
                continue;
            res++;
            st[p.row][p.col] = true;
            for (int i = 0; i < 4; i++) {
                int a = p.row + dx[i], b = p.col + dy[i];
                if (a >= 0 && a < rows && b >= 0 && b < cols)
                    queue.offer(new pair(a, b));
            }
        }
        return res;
    }

class pair{
    int row;
    int col;
    pair(int x,int y){
        row = x;
        col = y;
    }
    int getS(int x){
        int sum = 0;
        while (x > 0){
            sum = sum + (x % 10);
            x /= 10;
        }
        return sum;
    }
}
}