abcnow

三个红色和两个黑色
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$ C- w- v; _7 n9 \2 `tvb now,tvbnow,bttvb最后那个说我不知道我戴什么颜色帽子.5.39.217.76+ v/ Y; t0 P0 B
- 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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8 p4 Y# L& C, R  s& Q中间那个说我也不知道我戴什么颜色帽子.公仔箱論壇/ r  ?6 t7 u6 k, K8 Y0 H
- 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.
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但是第一个说我知道我戴什么颜色帽子.
7 Q5 m, U" E8 T' X& y公仔箱論壇- #1 must be wearing RED