八 20
原题：http://www.puzzleup.com/2010/puzzle/?224
You are going to place all numbers from 1 to 16 on a 4x4 chessboard such that all consecutive number pairs (1-2, 2-3, ..., 15-16) will be on the neighboring cells (left-right-top-down).
In how many different ways can this be done?
If the question was asked for a 2x2 chessboard, the answer would be 8.
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八月 29th, 2010 at 1:17 下午
晕了，本来还想试试自己的水平。结果一看，题目都是英文的，直接歇菜。
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