There is 12 balls.. divide them into piles of 4+ p& V: ^7 X8 u# N7 k9 S
so 3 groups for 4..name is A,B,C
1 k, K$ x6 e: w* w5.39.217.77case 1: tvb now,tvbnow,bttvb P& a7 N( x2 t+ X6 O E9 n
measure A -- B 3 m9 z1 o4 K8 \; ]( x1 K) C+ D
A or B is heavier 5.39.217.77; p% j5 A7 t- U; F( w" a
divide that group into 2 by 2tvb now,tvbnow,bttvb6 w# t4 M$ l$ }0 f
then divide heavier group into 1 by 1
) K6 _- Y$ p, \8 r0 O( d3 s5.39.217.77
! E+ v& J( ]7 M+ \. z* q5.39.217.77case 2:
3 Q y. _7 h' O$ e8 ~/ Y% s公仔箱論壇A and B is the same.. therefore C has the heavier ball9 J1 z" _( A4 x1 |, h/ G
divide C into 2 by 25.39.217.778 Q- Q+ r& h( l- o! k5 A& j d d' S y
then divide heavier group into 1 by 1..
" Q% `% H& B6 C4 ^+ M& P% P, J5.39.217.774 Z% L7 |1 v T+ `) g+ [2 ^. A4 x) x
got it in 30 seconds.. not so hard -.-' |
發表於 2006-12-8 01:06 PM
| 