fellatioho

put 3 balls on each side,
2 z- G5 q0 P" M7 g. P- n  cif balance, we can prove that all 6 balls on the 天平 is normal, ; R/ L2 h( L( B% j  n
if not balance, we can prove that the 6 balls outside the 天平 is normal.& r( N$ t- H! b/ }7 A% G) _. b4 x
then use the proved-normal ball on one side and put the other ball on other side
0 m2 n$ L4 M# ^% Q; X! Ato determine the abnormal is heavy and light