description: https://leetcode.com/problems/unique-paths/ 机器人从一堆方格的左上角走到右下角,只能往右或者往下走 ,问有几种走法,这个加了难度,在矩阵中加了障碍物 Note: Example: Example 1: Input: [ [0,0,0], [0,1,0], [0,0,0] ] Output: 2 Explanation: There is one obstacle in the middle of the 3x3 grid ab…