gensy850711

first divide it into 3 groups... 4 for each group...
; ?# j" x6 x% `" F# A2 }8 W6 p" itvb now,tvbnow,bttvbden 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...
) a4 `3 F' N. G" _/ pden... left 4 balls...公仔箱論壇( v6 ?! ?+ p, S1 e/ X. B
when u use tat 3 groups to test... u oredi know it is heavier or not...6 v% a3 @4 o; u0 x8 E$ ]+ Y5 f. K" w7 i
so when testing these 4 balls... u juz nit 2 find out the heavier or lighter 1...
' @9 E' Z, x! j2 Ftake the heavier or lighter 1... throw away tat 2 normal ball...
! |7 q/ J% \' G1 ?: xtvb now,tvbnow,bttvbden u juz nit 2 test the last 2 balls...
, m8 g9 ^: {3 B- o/ Q5 Otvb now,tvbnow,bttvbsame for now... take the heavier or lighter 1...