剑指 Offer 13. 机器人的运动范围——广度优先（BFS）

解题思路

广度优先搜索

代码

class Solution {
public:
    int x=0,y=0,now;
    int sum = 0;
    queue<int> q;
    bool vis[10000];
    int getDigitSum(int x){
        int ans = 0;
        while(x){
            ans+=x%10;
            x/=10;
        }
        return ans;
    }

    int movingCount(int m, int n, int k) {
        q.push(0);
        memset(vis,0,sizeof(vis));
        vis[0]=true;
        while(!q.empty()){
            now = q.front();
            ++sum;
            q.pop();
            x = now/n;
            y = now%n;
            if(x<m-1&&!vis[(x+1)*n+y]&&getDigitSum(x+1)+getDigitSum(y)<=k){
                q.push((x+1)*n+y);
                vis[(x+1)*n+y] = true;
            }
            if(y<n-1&&!vis[x*n+y+1]&&getDigitSum(x)+getDigitSum(y+1)<=k){
                q.push(x*n+y+1);
                vis[x*n+y+1] = true;
            }

        }
        return sum;
    }
};