-b1 b1 0···0 00 -b2 b2···0 0 0 0 0···-bn bn1 1 1 ... 1 1 所有列加到第1列, 再按第1列展开D = (-1)^(n+1+1) * (n+1) *b1b2...bn= (-1)^n * (n+1) *b1b2...bn
不知道，太深奥了
