There is 12 balls.. divide them into piles of 4 
, Y0 T' L+ n6 n0 Y  n: K: Uwww3.tvboxnow.comso 3 groups for 4..name is A,B,CTVBNOW 含有熱門話題,最新最快電視,軟體,遊戲,電影,動漫及日常生活及興趣交流等資訊。; @" T9 t2 Y9 ^. m! Z 
case 1: & s: Z/ E# m) R# w( S9 M 
measure A -- B www3.tvboxnow.com5 D. ]2 s0 m7 O. h+ [ 
A or B is heavier  
; S4 ^* e6 \% y' x4 ^tvb now,tvbnow,bttvbdivide that group into 2 by 2: g" u0 a% \6 K7 e/ N 
then divide heavier group into 1 by 1 
) c( E3 t& [5 }/ P3 P9 N8 NTVBNOW 含有熱門話題,最新最快電視,軟體,遊戲,電影,動漫及日常生活及興趣交流等資訊。 
+ h& V9 n2 j3 j$ P* CTVBNOW 含有熱門話題,最新最快電視,軟體,遊戲,電影,動漫及日常生活及興趣交流等資訊。case 2:tvb now,tvbnow,bttvb) W( @/ R) O% t; ?1 v8 H4 y& A 
A and B is the same.. therefore C has the heavier balltvb now,tvbnow,bttvb1 ?. X, p+ k0 Q4 v 
divide C into 2 by 2 
# K+ _" I# Y! y( `' ~tvb now,tvbnow,bttvbthen divide heavier group into 1 by 1..TVBNOW 含有熱門話題,最新最快電視,軟體,遊戲,電影,動漫及日常生活及興趣交流等資訊。' k4 {$ y3 M+ e( k% ? 
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got it in 30 seconds.. not so hard -.-' |