# List create [[0..1][0..2]] + [[0..7][0..9]] = [[[ 0..7 ][ 0..7 ]][[ 0..9 ][ 0..9 ][ 0..9 ]]]

Hi all!!
I want to make friends between two lists and get the following result:
[ [ [ 0…7 ] [ 0…7 ] ] [ [ 0…9 ] [ 0…9 ] [ 0…9 ] ] ]
is it possible?

Things tend to get more confusing if you mix list levels and lacing. You shouldn’t need to do that in most cases.

Just `@L1` for the `geometry` input should get you what you need as that’s going to treat the `@L1` items as individual inputs from `PolyCurve.Curves` and match the existing structure of `Curve.PointAtSegmentLength`.

then I will have a correspondence of each with each, and I need to 0List in PolyCurve.Curves to interact only 0List Curve.PointAtSegmentLength and 1List - 1List respectively

It’s important to understand that not all structures are possible with list levels for every node (based on input structure) due to how each node’s inherent “list comprehension” works. You can essentially force the input structure the node “sees” but you can’t change how it treats that structure. (Sometimes lacing can finish things off for you but mixing the two typically doesn’t get you what you want.)

In cases like these, I always suggest two alternatives:

1. Use python. You can control the exact looping or list comprehension you need to get the outcome you want.
2. When in doubt. Match your list structures exactly. You will never go wrong with a 1-to-1 input structure. You can usually get there by cycling or duplicating the shorter input list(s) to match the longest.
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Thank you for detailed response!!
I found a solution, but I’m not sure if it’s the best one.
I think it’s time to start learning phyton)

Yes, and for those of us challenged by complicated Python list manipulation, I suggest asking some AI tools how to do it.

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