gensy850711

first divide it into 3 groups... 4 for each group...5.39.217.776 t2 Q$ ~$ a$ i5 y7 y7 a  @4 Z% }
den use 2 groups to test... if the weight is same... den throw away these 2 groups.. if not... use another 1 group to test with tat 2 groups... throw away the same weight groups...1 F0 L% _; B0 w0 i& p' T
den... left 4 balls...# ^8 `( y' X8 g5 F+ O% h+ S
when u use tat 3 groups to test... u oredi know it is heavier or not...; g% b3 G/ \' M8 h
so when testing these 4 balls... u juz nit 2 find out the heavier or lighter 1...
9 F" ~( K+ o: a5.39.217.77take the heavier or lighter 1... throw away tat 2 normal ball...公仔箱論壇* j* u8 [9 F+ f! R% [. c
den u juz nit 2 test the last 2 balls...' d- U- ], ?  y8 N- `1 Q9 k3 R
same for now... take the heavier or lighter 1...