2（x＋1）=12/i7f+X.e5B7`,y2l:K/J0e:T7S2y2|6l'k
x=(n)r)C.{:f'B4P;k:\)p8q/v4_4j7d/i7f+X.e5B7`,y2l:K/J0e:T7S2y2|6l'k