Two-State Spin System graph G=(V,E)2 states {0,1} configuration o:V→{0，l} A= [=眼 contributions of local interactions: 020 weight: w(o）=A(),o(u） (u,v)∈ETwo-State Spin System A = ￾ A0,0 A0,1 A1,0 A1,1 ￾ = ￾ ￾ 1 1 ￾ ￾ 2 states {0,1} configuration ￾ : V ￾ {0, 1} graph G=(V,E) contributions of local interactions: weight: w(￾) = ￾ ￾ 1 ￾ (u,v)￾E A￾(u),￾(v)