1. If there are no direct connections from u_q to nodes in V _i(i≠q), we first propagate probability to other nodes in G_q from u_q via breadth-first-search layer by layer until we reach a node which has cross-edges to nodes in V _i. Then we initialize x_i⁽⁰⁾ = S_q→iP_q^te_q, where t is the number of hops that we first reach the effective node from u_q in G_q.