leetcode63

class Solution:
    def uniquePathsWithObstacles(self, obstacleGrid: List[List[int]]) -> int:
        m = len(obstacleGrid)
        n = len(obstacleGrid[0])
        dp = [[0 for _ in range(n)]for _ in range(m)]
        for j in range(n):
            if obstacleGrid[0][j] == 0:
                dp[0][j] = 1
            else:
                break
        for i in range(m):
            if obstacleGrid[i][0] == 0:
                dp[i][0] = 1
            else:
                break
        for i in range(1,m):
            for j in range(1,n):
                if obstacleGrid[i][j] == 0:
                    dp[i][j] = dp[i-1][j] + dp[i][j-1]
                else:
                    dp[i][j] = 0
        return dp[m-1][n-1]

在leetcode62的基础上，增加对障碍物的判断。