Check multiple items for presents across multiple lists

[m.shcheblykin (Maksym S.)]

Hello dear experts,
Can you please advise how in Grasshopper I can check if an item exist in multiple lists.
Lets say I have items list1 = [ A, B, C, D] and I have a list of lists list2 = [ [1,B,10,D], [10,K,A] ,[C,D,22,99,43] ]
I need to check each item from the list1 if it can be found in any sub list from the list2.
in the return I am okay with a list of True / False results for each item from the list1.
Example for the Item A:
A: [False, True, False] → Item A can be found only in the 2nd sub list of the list2.
Same results I need for all other items in the list1. So I will have a nested list with True/False values
A: [False, True, False]
B: [True, False, False]
C: [False, False, True]
D: [True, False, True]

I know how it can be done in Dynamo but Grasshopper works in a different way

[Joseph_Oster]

It would be so much easier to answer this question if you posted a GH file that contains your sample data instead of requiring each person to re-create those lists.

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@m.shcheblykin

Lets say I have items list1 = [ A, B, C, D] and I have a list of lists list2 = [ [1,B,10,D], [10,K,A] ,[C,D,22,99,43] ]

What a pain It would be so much easier if you posted this GH file:

[m.shcheblykin (Maksym S.)]

Hi Joseph,
Thank you for your reply,
The actual file and the subject is much more complex. The data described in the post just to explain the nature of an issue. I do not need anyone to do the project for me here. I need just to see which how with grasshopper components I can force grasshopper check if A, B, C, D exist in other lists. You have recreated what the described sample only. It can be anything else. We can search for Bananas and Oranges instead of A,B,C,D

[maje90 (Riccardo Majewski)]

@m.shcheblykin

It can be anything else.

It’s hard to program without knowing the type of objects to compare/test.

Here an example comparing strings:

multiple equality tests.gh (9.1 KB)

The “test” is a simple:

  private void RunScript(string x, string y, ref object R)
  {
    R = x == y;
  }

(there is not a native component for comparing strings…)

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Can you show a understandable picture of how was the solution with Dynamo?
I’ve never used it or Revit, but i’m curious…

[Joseph_Oster]