Two graphs G_1 = (V_1, E_1) and G_2 = (V_2, E_2), such that V_1 = V_2 = {1, 2, ..., n} are isomorphic if there is a one-one, onto function pi: {1, 2, ...., n} rightarrow {1, 2, ..., n} such that for every elementof E_1 elementof E_2 Show that the following decision problem in in NP. Problem: Isomorphism Input Instance: Two graphs G_1 = (V_1, Ei_1) and G_2 = (V_2, E_2) where V_1 = V_2 = {1, 2, ..., n} Decision: Are G_1 and G_2 isomorphic