Hi,

I am trying to solve the Path Sum II problem in C and the function is given as follows

```
/**
* Return an array of int arrays of size *returnSize.
* The sizes of the int arrays are returned in *columnSizes.
*/
int **pathSum(int candidates[], int n, int target, int *columnSizes, int *returnSize) {
}
```

My question is the tree expected to be stored as for a node at index i left child at 2*i and right child at 2*i+1,

also what is the value for NULL in the candidate ?

Regards,

Arka