Introduction
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Requirement
An encrypted file, cryptfile1.txt, is given. Your task is to decrypt it. The file was encrypted using some substitution algorithm. The easiest way to break such encryptions is by an analysis of letter frequency. You can go to the library or the Web and get information on the relative frequency of letters in the English language. A program, LetterCount.java, is also given which would allow you to find this yourself. You would simply have to choose a source text file that is sufficiently long and sufficiently representative of English that the relative frequencies of letters in it is pretty much the same as the relative frequencies given in published sources. The real value of LetterCount.java is that it provides sample code that you code adapt to decryption purposes. This encryption is simple enough that in theory you could do it by hand. If you find that your initial attempt by hand is netting nothing, you may want to write a program to help. You should hand in the results of your decryption effort.
Analysis
Java，，，
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pmefp wunhi igsrh lxjsv xlmwg hyhigrkfmk zsgep gsvhw hbdth swxtv shmkmotckt euiig hgnmo ceess theoh snegseepws lmrsw mwgep piheg vewlx lexekmepmr skmkw sjxlm wfvii heziv ekisrehcwu xlias hoofo mkveg sette adrlaxlivi lmrom fivxl lsphw ytsjv vphwq
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apple，cable。
Tis
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