first, compare 6 and another 6. they must have difference.
9 y6 k3 D8 M% w0 Z1 y( tsecond, divide those 6 heavier one into two, each has 3. u will find difference again.公仔箱論壇6 e) z1 P+ G5 Y
third time, if u put 2 and they are equal, u will know the different one.公仔箱論壇9 e/ o. ~3 q! C' @$ K9 O
so easy.... |