The test cases of [[0],[0],[0],[0],[0],[0],[0],[0],[0],[0],[0],[0],[0],[0],[0],[0],[0],[0],[0],[0],[0]] returned runtime error

Code is below:

```
class Solution {
public:
int uniquePathsWithObstacles(vector<vector<int> > &obstacleGrid) {
vector<vector<int>> myth(obstacleGrid.size(), vector<int>(obstacleGrid[0].size(),-1));
for(int i = 0;i<myth.size();i++)
for(int j = 0;j<myth[0].size();j++)
{
if(obstacleGrid[i][j]==0)
myth[i][j] = -1;
else
myth[i][j] = 0;
}
myth[0][0] = 1;
for(int i = 1;i<myth.size();i++)
{
if(myth[i][0]==0)
continue;
myth[i][0] = myth[i-1][0];
}
for(int i = 1;i<myth[0].size();i++)
{
if(myth[0][i]==0)
continue;
myth[0][i] = myth[0][i-1];
}
for(int i = 1;i<myth.size();i++)
for(int j = 1;j<myth.size();j++)
{
if(myth[i][j] == 0)
continue;
myth[i][j] = myth[i-1][j]+myth[i][j-1];
}
return myth[myth.size()-1][myth[0].size()-1];
//return 1;
}
};
```