public class Solution {
    public int UniquePathsWithObstacles(int[][] obstacleGrid) {
        int n = obstacleGrid.Length, m = obstacleGrid[0].Length;
        // 到点n,m不同路径数量
        int[,] dp = new int[n, m];
        // 遇到障碍物跳过列剩余元素
        for (int i = 0; i < n; i++){
            if (obstacleGrid[i][0] == 1) break;
            dp[i, 0] = 1;
        }
        // 遇到障碍物跳过行剩余元素
        for (int j = 0; j < m; j++){
            if (obstacleGrid[0][j] == 1) break;
            dp[0, j] = 1;
        }

        for (int i = 1; i < n; i++){
            for (int j = 1; j < m; j++){
                if(obstacleGrid[i][j] != 1){
                    dp[i, j] = dp[i - 1, j] + dp[i, j - 1];
                }
            }
        }

        return dp[n - 1, m - 1];
    }
}