Puzzleup 2020 (1) Tetrahedron Travel - 拼圖

題目網址: https://www.puzzleup.com/2020/
https://www.puzzleup.com/2020/puzzle/?1
答題時限: 11月５日７ＰＭ－比賽結束（約12月30日）
加分時限: 11月５日７ＰＭ－11月10日６：５９ＰＭ

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　 　　 　　
另依題目的難易有額外加分（如有８０％的人這題答錯，答對者加８０分）　　

◆TETRAHEDRON TRAVEL

https://www.puzzleup.com/2020/img/puzzle/2020/01.jpg

You will make a travel through the edges of two tetrahedrons (ABCD, and CDEF)
joined as shown in the figure.

- You will start on A, and finish on F.
- You can visit the vertices more than once except the finishing vertex F.
- You can't pass through the edges more than once.

In how many different ways can this travel be done?

Note: Two travels having same edges in different order will be considered as
different.

你將從上圖這兩個正四面體 (ABCD 及 CDEF) 在一個邊相接的圖形的邊上進行移動。

- 路線從 A 開始，到 F 結束。
- 除了 F 之外的任一頂點皆可以經過多於一次。
- 任一條邊不能經過多於一次。

試問如此的移動有多少種不同的走法？

注意: 兩個走法若僅是經過的邊順序不同依然視為不同走法。

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第一題是個舊題形回顧, 之前出在 2015 Q9 和 2016 Q10

那因為同樣幾乎一字不改我就把舊翻譯拿來用了 XD

--
'You've sort of made up for it tonight,' said Harry. 'Getting the
sword. Finishing the Horcrux. Saving my life.'
'That makes me sound a lot cooler then I was,' Ron mumbled.
'Stuff like that always sounds cooler then it really was,' said
Harry. 'I've been trying to tell you that for years.'
-- Harry Potter and the Deathly Hollows, P.308

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