package leetcode
func uniquePathsWithObstacles(obstacleGrid [][]int) int {
if len(obstacleGrid) == 0 || obstacleGrid[0][0] == 1 {
return 0
}
m, n := len(obstacleGrid), len(obstacleGrid[0])
dp := make([][]int, m)
for i := 0; i < m; i++ {
dp[i] = make([]int, n)
}
dp[0][0] = 1
for i := 1; i < n; i++ {
if dp[0][i-1] != 0 && obstacleGrid[0][i] != 1 {
dp[0][i] = 1
}
}
for i := 1; i < m; i++ {
if dp[i-1][0] != 0 && obstacleGrid[i][0] != 1 {
dp[i][0] = 1
}
}
for i := 1; i < m; i++ {
for j := 1; j < n; j++ {
if obstacleGrid[i][j] != 1 {
dp[i][j] = dp[i-1][j] + dp[i][j-1]
}
}
}
return dp[m-1][n-1]
}