063. Unique Paths II.cpp

class Solution {
public:
    int uniquePathsWithObstacles(vector<vector<int>>& obstacleGrid) {
        int m = obstacleGrid.size(), n = obstacleGrid[0].size();
        vector<int>dp(n);
        dp[0] = 1;
        for (int i = 0; i < m; ++i) {
            for (int j = 0; j < n; ++j) {
                if (obstacleGrid[i][j] == 1) {
                    dp[j] = 0;
                } else {
                    dp[j] += dp[j - 1];
                }
            }
        }
        return dp[n - 1];
    }
};