三个红色和两个黑色
' I! ]% [* M! \) L- M5 O
4 K+ Y3 y' ^( |$ @* \2 Q3 ^最后那个说我不知道我戴什么颜色帽子.+ H% q/ e, ~2 [
- the front #1 , #2 must not be black/black. Otherwise, #3 will know he is red. #1/#2 must be red/red or red/black or black/red.! R5 b y" n3 O1 J( K; c
- P) b' ^! d7 m. T. S: T8 Z- q/ u: P
中间那个说我也不知道我戴什么颜色帽子.- {4 K9 d7 D! B" Z$ b
- for #2, if he see #1 wearing black, he can be sure he is red. since #2 cannot be sure, then #1 must NOT be wearing black.6 U* w' s) B1 l5 b+ {8 [
3 |8 d' v/ G- Q7 t- y
但是第一个说我知道我戴什么颜色帽子.
; M. h+ q6 c1 Z# g- ]1 r9 @- #1 must be wearing RED |
發表於 2008-12-3 10:06 AM
| 
