```
public int uniquePathsWithObstacles(int[][] obstacleGrid) {
if (obstacleGrid == null || obstacleGrid.length == 0 || obstacleGrid[0].length == 0) return 0;
int m = obstacleGrid.length;
int n = obstacleGrid[0].length;
for (int i = 0; i < m; i++)
for (int j = 0; j < n; j++) {
obstacleGrid[i][j] = 1 - obstacleGrid[i][j];
if (obstacleGrid[i][j] > 0) { //not obstacke
if (i != 0 || j!= 0)
obstacleGrid[i][j] = ((i > 0) ? obstacleGrid[i-1][j] : 0) + ((j > 0) ? obstacleGrid[i][j-1] : 0);
}
}
return obstacleGrid[m-1][n-1];
}
```