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三个红色和两个黑色
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最后那个说我不知道我戴什么颜色帽子.
2 ?7 q7 W, v6 H4 z3 f公仔箱論壇- 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.
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中间那个说我也不知道我戴什么颜色帽子." c: K. L5 E3 `; b$ d6 z2 f, w9 {4 x
- 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.公仔箱論壇. x1 }  j* e+ P+ c% Y
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但是第一个说我知道我戴什么颜色帽子.
. x+ Q7 h9 I6 l( E3 \公仔箱論壇- #1 must be wearing RED