LeetCode 1293. Shortest Path in a Grid with Obstacles Elimination

题目

非常简单的BFS 暴搜

struct Node
{
    int x;
    int y;
    int k;
    int ans;
    
    Node(){}
    Node(int x,int y,int k,int ans)
    {
        this->x=x;
        this->y=y;
        this->k=k;
        this->ans=ans;
    }
};
class Solution {
public:
    int dir[4][2]={{0,-1},{0,1},{1,0},{-1,0}};
    int vis[105][105];
    int vis2[105][105];
    int n,m;
    vector<vector<int>> map;
    queue<Node> q;
    int shortestPath(vector<vector<int>>& grid, int k) {
        
        n = grid.size();
        m = grid[0].size();
        memset(vis,-1,sizeof(vis));
        
        q.push(Node(0,0,k,0));
        
        int ans = -1;
        
        while(!q.empty())
        {
            
            Node term = q.front();
            
            q.pop();
            
            if(term.x == n-1 && term.y==m-1)
            {
                return term.ans;
            }
            
            for(int i=0;i<4;i++)
            {
                int xx = term.x +dir[i][0];
                int yy = term.y +dir[i][1];
            
                if(xx < 0 || yy < 0 || xx >= n || yy >=m)
                    continue;
                        
                if(vis[xx][yy]!=-1&&vis[xx][yy]>=term.k)
                    continue;

                if(grid[xx][yy]==1)
                {
                    if(term.k>0)
                    {
                        vis[xx][yy]=term.k-1;
    
                        q.push(Node(xx,yy,term.k-1,term.ans+1));
                    }
                }
                else
                {
                    vis[xx][yy]=term.k;
  
                    q.push(Node(xx,yy,term.k,term.ans+1));
                }

            }
        }
        
        return -1;
        
        
    }
    
    
    
};

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转载自www.cnblogs.com/dacc123/p/12049729.html