leetcode 每日一题 63. 不同路径 II

动态规划

思路：

参考62. 不同路径

代码：

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