Curve solid intersection overwriting

Hi i have a problem with understand how “curve.solidintersection” works. I have only 5 pipes as input but i get 20 intersection.

I try to deal with this and choose one list [1] but it doesn’t work if i change elements. Do you know how to deal with this problem?

My whole script:

Ok i understand my stupid question… My list has the same walls few times. I removed them from list… all works fine :slight_smile: