i find one solution that is similar
& {) Z3 ?9 I) v# J2 E. I D0 Wtvb now,tvbnow,bttvbbut i can't specify the heavier one is abnormal or the lighter one is abnormal when the case that has only two balls left....tvb now,tvbnow,bttvb# \' @# r) p; Q6 b g" v: N
maybe there is a better one, let me see sin |