Puzzleup 2011 (19) Eight Cubes - 拼圖

題目網址: www.puzzleup.com/2011/puzzle/?237
加分時限: 12/1 7PM - 12/6 7PM

答對可得基本分１００分。答案可上傳５次，每改１次答案從基本分扣２０分。　
比賽期間內可隨時上傳答案，加分時限內答對第ｎ天加（６－ｎ）分　 　　 　　
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◆Eight Cubes

You have eight identical unit cubes, each of which is given a different
letter. These eight unit cubes are conjoined to form a 2x2x2 cube. You will
move on these cubes and produce 8-letter codes.

‧ You can begin your tour on any unit cube.
‧ You can pass from that cube to any of the neighboring (ie. cubes sharing a
common surface) cubes.
‧ You will visit each unit cube exactly once.

How many different codes you can produce?

你有八個一模一樣的單位立方體，每個都標一個各不相同的字母。
這八個立方體合成一個2x2x2的立方體。
依照以下的方式得出一個八字母的字串：

‧ 從任一個單位立方體做為起點；
‧ 每次移動可以到達相鄰的立方體 (即共面的立方體)；
‧ 要經過八個立方體正好一次。

試問如此一來能夠得到多少種字串？

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又有種熟悉感...

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LPH [acronym]
= Let Program Heal us
-- New Uncyclopedian Dictionary, Minmei Publishing Co.

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