Dynamic Programming

```
func uniquePathsWithObstacles(obstacleGrid [][]int) int {
var M [100][100]int
m := len(obstacleGrid)
n := len(obstacleGrid[0])
if obstacleGrid[0][0] == 0 {
M[0][0] = 1
}
for j := 1; j < n; j++ {
if obstacleGrid[0][j] == 0 {
M[0][j] = M[0][j-1]
}
}
for i := 1; i < m; i++ {
if obstacleGrid[i][0] == 0 {
M[i][0] = M[i-1][0]
}
}
for i := 1; i < m; i++ {
for j := 1; j < n; j++ {
if obstacleGrid[i][j] == 0 {
M[i][j] = M[i-1][j] + M[i][j-1]
}
}
}
return M[m-1][n-1]
}
```