Select the same node on adjacent faces

Dear all,

Given a mesh 3D, I need to select one node in each face. Given 2 adjacent faces, how to be sure that we select the same node on these two faces ?

I put in attachment my test case. You will find the way I select one node in each face (at the line 37) and the routine to check if the chosen node is the same.

In my code, the lines to be modified is in the section " SELECT ONE NODE ON EACH FACE"

Thank you in advance,


Best regards,