假設原本有$10, 用$8買雞, 剩$2
8 r0 G' e* Z$ k; S0 I$ R! W3 vos.tvboxnow.com之後$9賣出, $2+$9 = $11
0 N# I( |9 e. T7 b6 x1 V; f' m+ ^' i: K O再用$10買雞, $11-$10 = $1
) {1 T8 ^7 w9 H& G" `0 p) P又再以$11賣出, $1+$11 = $12tvb now,tvbnow,bttvb f3 d% z; j- h4 w5 ^" o
$12-$10 = 賺$2 |