leetCode63. 不同路径 II
题目思路

代码

class Solution {
public:
    int uniquePathsWithObstacles(vector<vector<int>>& ob) {
        int n = ob.size();
        if(!n) return 0;

        int m = ob[0].size();

        vector<vector<int>> f(n,vector<int>(m));

        for(int i = 0; i < n; i++){
            for(int j = 0; j < m; j++){
                if(!ob[i][j]){
                    if(!i && !j) f[i][j] = 1;
                    else{
                        if(i) f[i][j] += f[i - 1][j];
                        if(j) f[i][j] += f[i][j - 1];
                    }
                }
            }
        }

        return f[n - 1][m - 1];
    }
};