i find one solution that is similar# `+ \1 W: A4 c! L6 z( ~" m
but 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) p8 M/ o$ Q3 ^" U2 T z+ h# h
maybe there is a better one, let me see sin |