stupid818

first, compare 6 and another 6. they must have difference. 公仔箱論壇) ~* a. e/ k: N$ U
second, divide those 6 heavier one into two, each has 3. u will find difference again.
  w3 `# U$ H% @: q9 R公仔箱論壇third time, if u put 2 and they are equal, u will know the different one.
8 }. e( }/ T7 B5 t3 j9 @9 xso easy....