def main():
random.seed(42)
for i in range(15): #run 15 tests
message = "ABCDEFGHIJKLMNOPQRSTUVWXYZ" * random.randint(4, 40)
message = list(message)
random.shuffle(message)
message = ''.join(message)
print("Test #%s: %s..." % (i + 1, message[:20]))
for key in range(1,
math.ceil(len(message) / 2)): #test all possible keys
ciphertext = TranspositionCipher.encryptMessage(key, message)
plaintext = TranspositionCipherDecrypt.decryptMessage(
key, ciphertext)
if plaintext != message:
print("ERROR // Test #%s using key #%s failed!" % (i + 1, key))
print("Message reads: %s" % (message))
print("Decryption reads: %s" % (plaintext))
sys.exit(0)
print("Test passed.")
def main():
#inputFilename = 'frankenstein.txt'
# to decrypt, next line must run
inputFilename = 'frankenstein.encrypted.txt'
outputFilename = 'frankenstein.decrypted.txt'
myKey = 10
myMode = 'decrypt'
# if input file does not exist program leaves early.
if not os.path.exists(inputFilename):
print "the file %s does not exist. Qutting..." % (inputFilename)
sys.exit()
# if output file exists, give user a chance to continue
if os.path.exists(outputFilename):
print "this will overwrite the file %s. (C)ontinue or (Q)uit?" % (outputFilename)
response = raw_input('> ')
if not response.lower().startswith('c'):
sys.exit()
# read in message from input file
fileObj = open(inputFilename)
content = fileObj.read()
fileObj.close()
print '%sing...' % (myMode.title()) # converts lowercase to first letter capitalized
startTime = time.time()
if myMode == 'encrypt':
translated = TranspositionCipher.encryptMessage(myKey, content)
elif myMode == 'decrypt':
translated = decryptTransposition.decryptMessage(myKey, content)
totalTime = round(time.time() - startTime, 2)
print '%sion time: %s seconds' % (myMode.title(), totalTime)
# write out translated message to a file
outputFileObj = open(outputFilename, 'w')
outputFileObj.write(translated)
outputFileObj.close()
print 'Done %sing %s (%s characters).' % (myMode, inputFilename, len(content))
print '%sed file is %s.' % (myMode.title(), outputFilename)
def encryptMessage(message, key, alphabet):
key1 = len(message)
new_alphabet = AffineCipher.encryptMessage(alphabet, key1, alphabet)
out1 = TranspositionCipher.encryptMessage(message, key)
num = len(new_alphabet)
count = 0
out2 = ''
first_symbol = True
for symbol in out1:
symbol_index = new_alphabet.find(symbol)
if symbol_index > -1:
symbol_index += new_alphabet.find(new_alphabet[count])
if first_symbol is True:
symbol_index += len(message)
first_symbol = False
out2 += new_alphabet[(symbol_index) % num]
else:
out2 += symbol
count = (count + 1) % num
return out2
