LeetCode Q63: Unique Paths II

Follow up for "Unique Paths":

Now consider if some obstacles are added to the grids. How many unique paths would there be?

An obstacle and empty space is marked as 1 and 0 respectively in the grid.

For example,

There is one obstacle in the middle of a 3x3 grid as illustrated below.

[
  [0,0,0],
  [0,1,0],
  [0,0,0]
]

The total number of unique paths is 2.

Note: m and n will be at most 100.

	class Solution {
	public:
	int uniquePathsWithObstacles(vector<vector<int> > &obstacleGrid) {
	int m = obstacleGrid.size() , n = obstacleGrid[0].size();
	vector<vector<int>> dp(m+1,vector<int>(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];
	}
	};

view raw Q63UniquePathII.cpp hosted with ❤ by GitHub