// 63. Unique Paths II #include "leetcode.h" /* You are given an m x n integer array grid. There is a robot initially located at the top-left corner (i.e., grid[0][0]). The robot tries to move to the bottom-right corner (i.e., grid[m - 1][n - 1]). The robot can only move either down or right at any point in time. An obstacle and space are marked as 1 or 0 respectively in grid. A path that the robot takes cannot include any square that is an obstacle. Return the number of possible unique paths that the robot can take to reach the bottom-right corner. The testcases are generated so that the answer will be less than or equal to 2 * 109. */ class Solution { public: int uniquePathsWithObstacles(vector> &obstacleGrid) { int m = obstacleGrid.size(), n = obstacleGrid[0].size(); vvd(int) dp(m + 1, vector(n + 1, 0)); dp[0][1] = 1; for (int i = 1; i <= m; ++i) for (int j = 1; j <= n; ++j) if (!obstacleGrid[i - 1][j - 1]) dp[i][j] = dp[i - 1][j] + dp[i][j - 1]; return dp[m][n]; } }; int main() { Solution obj; vvd(int) og1 = {{0, 0, 0}, {0, 1, 0}, {0, 0, 0}}, og2 = {{0, 1}, {0, 0}}; printf("%d\n", obj.uniquePathsWithObstacles(og1)); // expect: 2 printf("%d\n", obj.uniquePathsWithObstacles(og2)); // expect: 1 }