Minimum Path Sum

问题：从左上角到右下角的最小路径和

?

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17

class Solution { public:     int num[300][300];     int dfs(int x,int y,vector<vector<int> >&grid)     {         if(x==grid.size()-1 && y==grid[0].size()-1) return grid[x][y];         if(num[x][y]) return num[x][y];         int h1=99999,h2=99999;         if(x+1<grid.size())  h1=dfs(x+1,y,grid);         if(y+1<grid[0].size()) h2=dfs(x,y+1,grid);         return num[x][y]=min(h1,h2)+grid[x][y];     }     int minPathSum(vector<vector<int> > &grid) {         memset(num,0,sizeof(num));         return dfs(0,0,grid);     } };