I have a list of lists. It looks something like this:

```
[
    [4,7,9,10],
    [5,14,55,24,121,56, 89,456, 678],
    [100, 23, 443, 34, 1243,]
    ....
]

```

I want to iterate such that on every iteration I get the respective element of that index from all lists and if the list gets empty, drop it.

For instance, when index will be 0, I want a list that would extend (add) 4 from list 0,5 from list 1, 100 from list 2 (0th index of all list) and if the list gets empty (like list 0 will be fully covered after 3rd iteration, skip it. So iteration should skip this list and move on the next list.

So the output should look like: `[4,5,100, 7, 14, 23, 9, 55, 443, 10, 24, 34, 121, 1243, 56. 89, 456, 678]`

I want a list that extends these values.