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First solution in Clear category for ADFGVX Cipher by jcg
#http://www.checkio.org/mission/adfgvx-cipher/solve/
def encode(message="I am going",
secret_alphabet="dhxmu4p3j6aoibzv9w1n70qkfslyc8tr5e2g",
keyword="cipher",
debug=False):
if debug:
print("\n----------------\nCoding")
print("Message :", message)
# Our message is "I am going".
# First we must clean and process the message: "iamgoing".
# It should contain only digits and latin letters in lowercase.
# All other characters (such as punctuation) are skipped.
message0 = ''.join(filter(lambda x:x.isalnum(), message.lower()))
if debug:
print("Cleaned message :", message0)
# Then we fill the "adfgvx" table with our secret alphabet
# "dhxmu4p3j6aoibzv9w1n70qkfslyc8tr5e2g".
indexes = "ADFGVX"
adfgvx_table = [[secret_alphabet[6*i+j] for j in range(6)] for i in range(6)]
if debug:
print("ADFGVX table :")
print("\n".join(
('\\ ' + ' '.join(indexes),
' \\' + '--'*len(indexes) ) +
tuple(" ".join([indexes[i]+'|']+row) for i,row in enumerate(adfgvx_table))))
# Using this square, the message is converted to fractionated form (row-column):
message1 = ''
for x in message0:
i, j = 0, 0
while True:
if x == adfgvx_table[i][j]:
break
j = (j + 1) % len(adfgvx_table[i])
if j == 0:
i += 1
message1 += indexes[i] + indexes[j]
if debug:
print("Fractionated form :", ' '.join(message1[i:i+2] for i in range(0,len(message1),2)))
# Then, a new table is created with a key as the heading.
# Let's use 'cipher' as the key. If the key contains duplicated letters,
# the first one should be used. So, "checkio" becomes "chekio".
keyword = ''.join(sorted(set(keyword), key=lambda x:keyword.index(x)))
if debug:
print("No duplicate in keyword :", keyword)
nb_col = len(keyword)
nb_row = (len(message1)-1)//nb_col + 1
table1 = [[message1[nb_col*i+j] if nb_col*i+j < len(message1) else ''
for j in range(nb_col)]
for i in range(nb_row)]
if debug:
print("Table 1 :")
print('\n'.join((' '.join(keyword),'-'.join('-'*nb_col)) +
tuple(' '.join(row) for row in table1)))
# The columns are sorted alphabetically based on the keyword
# and the table changes to the new form.
sorted_kw = ''.join(sorted(keyword))
if debug:
print("Sorted keyword :", sorted_kw)
table2 = [[row[keyword.index(sorted_kw[c])]
for c in range(nb_col)]
for row in table1]
if debug:
print("Table 2 :")
print('\n'.join((' '.join(sorted_kw),'-'.join('-'*nb_col)) +
tuple(' '.join((row[i] or ' ')
for i in range(nb_col))
for row in table2)))
# Then it is read off in columns, in keyword order
# and the result is "FXGAFVXXAXDDDXGA".
message2 = ''.join(table2[i][j]
for j in range(nb_col)
for i in range(nb_row))
if debug:
print("Returned message :", message2)
return message2
def decode(message="FXGAFVXXAXDDDXGA",
secret_alphabet="dhxmu4p3j6aoibzv9w1n70qkfslyc8tr5e2g",
keyword="cipher",
debug=False):
if debug:
print("\n----------------\nDecoding")
print("Message :", message)
# first no duplicate in keyword
keyword = ''.join(sorted(set(keyword), key=lambda x:keyword.index(x)))
if debug:
print("No duplicate in keyword :", keyword)
# then compute directly the table1... no proud of that code
sorted_kw = ''.join(sorted(keyword))
if debug:
print("Sorted keyword :", sorted_kw)
nb_col = len(keyword)
nb_row = (len(message)-1)//nb_col + 1
table1 = [[""]*nb_col for _ in range(nb_row)]
i = 0
for col in range(nb_col):
for row in range(nb_row):
# compute the final col for no sorted keyword
col2 = keyword.index(sorted_kw[col])
# if the final place is blank
if row * nb_col + col2 >= len(message):
continue
else: #place the letter
table1[row][col2]=message[i]
i += 1
if debug:
print("Table 1 :")
print('\n'.join((' '.join(keyword),'-'.join('-'*nb_col)) +
tuple(' '.join(row) for row in table1)))
# read the table1 to get the fractionned form
message1 = ''.join(''.join(row) for row in table1)
if debug:
print("Fractionated form :", ' '.join(message1[i:i+2] for i in range(0,len(message1),2)))
# finally, get the decrypted message
indexes = "ADFGVX"
adfgvx_table = [[secret_alphabet[6*i+j] for j in range(6)] for i in range(6)]
if debug:
print("ADFGVX table :")
print("\n".join(
('\\ ' + ' '.join(indexes),
' \\' + '--'*len(indexes) ) +
tuple(" ".join([indexes[i]+'|']+row) for i,row in enumerate(adfgvx_table))))
message0 = ''.join(adfgvx_table[indexes.index(message1[i])]
[indexes.index(message1[i+1])]
for i in range(0,len(message1),2) )
if debug:
print("Returned message :", message0)
return message0
if __name__ == '__main__':
assert encode("I am going",
"dhxmu4p3j6aoibzv9w1n70qkfslyc8tr5e2g",
"cipher") == 'FXGAFVXXAXDDDXGA', "encode I am going"
assert decode("FXGAFVXXAXDDDXGA",
"dhxmu4p3j6aoibzv9w1n70qkfslyc8tr5e2g",
"cipher") == 'iamgoing', "decode I am going"
assert encode("attack at 12:00 am",
"na1c3h8tb2ome5wrpd4f6g7i9j0kjqsuvxyz",
"privacy") == 'DGDDDAGDDGAFADDFDADVDVFAADVX', "encode attack"
assert decode("DGDDDAGDDGAFADDFDADVDVFAADVX",
"na1c3h8tb2ome5wrpd4f6g7i9j0kjqsuvxyz",
"privacy") == 'attackat1200am', "decode attack"
assert encode("ditiszeergeheim",
"na1c3h8tb2ome5wrpd4f6g7i9j0kjqsuvxyz",
"piloten") == 'DFGGXXAAXGAFXGAFXXXGFFXFADDXGA', "encode ditiszeergeheim"
assert decode("DFGGXXAAXGAFXGAFXXXGFFXFADDXGA",
"na1c3h8tb2ome5wrpd4f6g7i9j0kjqsuvxyz",
"piloten") == 'ditiszeergeheim', "decode ditiszeergeheim"
assert encode("I am going",
"dhxmu4p3j6aoibzv9w1n70qkfslyc8tr5e2g",
"weasel") == 'DXGAXAAXXVDDFGFX', "encode weasel == weasl"
assert decode("DXGAXAAXXVDDFGFX",
"dhxmu4p3j6aoibzv9w1n70qkfslyc8tr5e2g",
"weasel") == 'iamgoing', "decode weasel == weasl"
Sept. 26, 2014
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