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+from itertools import product,cycle,izip
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+
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+def loadWords():
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+ """
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+ Returns a list of valid words. Words are strings of lowercase letters.
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+
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+ Depending on the size of the word list, this function may
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+ take a while to finish.
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+ """
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+ print "Loading word list from file..."
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+ inFile = open("59_words.txt", 'r')
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+ wordList = inFile.read().split()
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+ print " ", len(wordList), "words loaded."
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+ return wordList
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+
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+wordList = loadWords()
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+
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+def getCipherList():
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+ """
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+ Returns cipher in encrypted list.
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+ """
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+ return open("cipher1.txt", "r").read().strip('\n').split(",")
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+
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+def isWord(wordList, word):
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+ """
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+ Determines if word is a valid word.
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+
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+ wordList: list of words in the dictionary.
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+ word: a possible word.
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+ returns True if word is in wordList.
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+
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+ Example:
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+ >>> isWord(wordList, 'bat') returns
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+ True
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+ >>> isWord(wordList, 'asdf') returns
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+ False
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+ """
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+ word = word.lower()
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+ word = word.strip(" !@#$%^&*()-_+={}[]|\\:;'<>?,./\"")
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+ return word in wordList
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+
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+def numWords(decryptedText):
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+ """ Returns the number of valid words there are in given text """
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+ decryptedList = decryptedText.split()
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+ wordCount = 0
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+
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+ for word in decryptedList:
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+ if isWord(wordList, word):
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+ wordCount += 1
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+
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+ return wordCount
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+
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+def ascii(cipherList):
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+ """ Takes list of ASCII codes as input, returns concatenated string """
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+ decryptedList = []
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+ for char in cipherList:
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+ decryptedList.append(chr(int(char)))
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+
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+ return "".join(map(chr, map(int, cipherList)))
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+
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+def decrypt(key):
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+ """ Decrypts story using given key using an XOR cipher """
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+ data = ascii(getCipherList())
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+ return "".join(chr(ord(x) ^ ord(y)) for (x,y) in izip(data, cycle(key)))
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+
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+def asciisum(text):
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+ """ Returns the sum of ASCII codes in a given string """
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+ text = list(text)
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+ text = map(ord, text)
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+ return sum(text)
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+
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+def main():
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+ """
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+ Main wrapper function.
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+
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+ Generates all possible keys, then iterates through them to find the one that
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+ decrypts the original ciphertext into the maximum number of English words.
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+ The function returns the sum of the ASCII codes of the resulting decrypted
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+ text.
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+ """
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+ lowercase = map(chr, range(97, 123))
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+
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+ # Generate a list of possible keys
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+ keylist = []
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+ for key in product(lowercase, repeat=3):
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+ keylist.append("".join(key))
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+
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+ currentNumWords = 0
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+ maxWords = 0
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+ bestKey = ""
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+
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+ for key in keylist:
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+ currentNumWords = numWords(decrypt(key))
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+ if currentNumWords > maxWords:
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+ maxWords = currentNumWords
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+ bestKey = key
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+
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+ return asciisum(decrypt(bestKey))
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+
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+print main()
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