Many shores, for instance, have oyster reefs that act as incredibly efficient natural coastal buffers. They are able to both redirect the wave energy and absorb up to 75 percent of it.
one of the simplest forms of substitution is called the Caesar shift cipher, so named because it was favored by Julius Caesar himself. It works by using the standard alphabet but shifting the letter it begins on by a set number of characters. So, if you shifted the alphabet three places then A=D, B=E, C=F and so on.
The other method, substitution, is a system wherein one letter stands for another. For instance, A=V, B=X and so on until every letter of the alphabet has a substitute pair, thereby forming a cipher alphabet. Since this process forms an alphabet that replaces the conventional one, it is referred to as a monoalphabetic cipher.
The result was cryptography, a field that simultaneously developed two distinct branches: transposition and substitution.
Notes
《碼書》热门书评
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关于后面的闯关
6有用 0无用 未敢 2015-01-17
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翻译功力稍微差了一点
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辗转买到的新书
4有用 0无用 Emma/点点滴滴 2007-06-24
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神奇的力量：智力
2有用 0无用 leostone86 2009-07-26
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Notes
0有用 0无用 Sheryl 2017-01-25
Many shores, for instance, have oyster reefs that act as incredibly efficient natural coastal buffers. They are able to both redirect the wave energy ...
