Algorithm 1: Indirect Opinion Path Search Algorithm

1: Initialization 2: Input: Opinion set G of nodes, Complete set of nodes V, Target node Vt. 3: Output: All indirect opinion paths Ws reaching the target node Vt. 4: for all element Vs //Consider nodes in set V, excluding Vt, as source nodes Vs 5:  Ws = [];     //Define the path set Ws for Vs. 6:  Opinion_Walk(G,Vs,Vt)  //Recursively search for vehicles that have interactions 7:  if Vs ≠ Vt and G[Vs]! = [] 8:   W←Vs;        //Add qualifying nodes to the path W 9:  for node in G[Vs] 10:  if node not in W and len(W) < 3 11:   Opinion_Walk(G,node,Vt); 12:   if len(W) == 3 and Vs == Vt //If an indirect path is found, add it to the path set Ws 13:   Ws←W;       //Add qualifying nodes to the path W 14:   end if 15:  end if 16:  end for 17:  end if 18: end for 19: return Ws 20: END