I m learning grasshopper by my own and trying to understand a few things about the list

I am actually doing this tutorial (link below)

My first question concern the connection of a line (see the tutorial at 5:35min)
I don t understand why i don t get the same result when i connect my line to the two different explode component.

I think i should have the same result as the second option for both. please see the shotsreen attached

Check your connections. It looks like you connected the endpoint of the line component to the wrong component (it passes very close to the correct place)

Your 1st question has to do with the Explode component automatically grafting each input:

1st Explode takes in a curve and returns a single list of N curve segments,

2nd Explode takes in those N curves and returns a Datatree structure with N branches and only one item per branch (since the segments can’t be divided further)

This means the downstream components will match things up differently - basically inputs are matched branch-by-branch and only broadcasted across lists:

What it happens is different and i don t understand the logic.
They don t reach all the points in a logic order and i find sometimes some lines which overlay and has the same length.

What happens is that each of the (N=1) branches from the grafted component B is being matched up with the (N=7) branch from component A. So there are 7 lines being drawn per branch, each connecting the same vertex of B with all 7 vertices of A. This happens 7 times for each branch of B, for total of 49 lines.

I realise using a closed polygon as an example might have been confusing, because the start and end point is repeated. That’s why you get N=7 for a hexagon, the center point isn’t involved at all.