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There were a number of ways of using this information to derive the state of the Enigma machine from which all those six-letter sequences had emanated.
利用这三张表，就有很多办法可以推导出当天的谜机的设定状态。
But particularly significant was a method which responded to the mechanical work of the cipher clerk, with a mechanised form of analysis.
其中最重要的一种方法，是通过一套机械的分析形式，来应对操作员的机械式工作。
They wrote these tables of letter connections in the form of cycles.
他们用轮换的形式来描述这些字母关系，
The cycle notation was common currency in elementary group theory.
这是基础群论中很常用的方法。
To bring the specific letter connection above into 'cycle' form, one would start with the letter A, and note that A was connected with R.
要把一组特定的字母关系表示为轮换形式，首先从字母A开始，记下A连着R，
Then R was connected with B, B with G, G with M, M with W, W with Z, Z with C, C with Z, Z with U, U with K, and K with A—making a complete 'cycle':
接着找到R连着B，以此类推B连着G, G连着M, M连着W, W连着T, T连着C, C连着Z, Z连着U, U连着K, K连着A，这样就形成了一个完整的轮换：
(A R B G M W T C Z U K). The complete connection could be written out as the product of four cycles:
（ARBGMWTCZUK）。所有的字母关系可以表示为4个轮换：
The reason for doing this was that the analysts had noticed that the lengths of these cycles (in this example, 11, 11, 2, 2) were independent of the plugboard.
这样做的原因是，分析人员发现，这些轮换的长度（在这个例子中是11, 11, 2，2）与配线板无关，它们只取决于盘位。
They would depend only upon the position of the rotors, the plugboard affecting which letters appeared in the cycles, but not how many.
配线板影响轮换中的字母，但不会影响轮换长度。
