python으로 vigenere solver 짜기

from math import *
from collections import Counter
 
f = open('./vigenere.txt','r')
encode=f.read()
f.close()
 
alphabetDict={1:'a',2:'b',3:'c',4:'d',5:'e',6:'f',7:'g',8:'h',9:'i',10:'j',11:'k',12:'l',13:'m',14:'n',15:'o',16:'p',17:'q',18:'r',19:'s',20:'t',21:'u',22:'v',23:'w',24:'x',25:'y',26:'z'}
 
def getGcd (a,b):
    while(a!=0):
      tmp=b%a
      b=a
      a=tmp
    return abs(b)
 
print '====================================================================================================================='
print '\n   Two letters\n'
print '====================================================================================================================='
print '\n'
 
string2=[]                                      
 
for i in range(1,27):                           
   for j in range(1,27):                         
         s=alphabetDict[i]+alphabetDict[j]       
         string2.append([encode.count(s),s])     
 
index2=[]                     
count=0
cha=[]
gcd2=[]
string2.sort(reverse=True)                       
 
for i in range(0,26*26):
  indexcount=0
  if string2[i][0]>26:               
    print '---------------------------------------------------------------------------------------------------------------------\n'           
    print " string : \"{}\", frequency : {}".format(string2[i][1],string2[i][0])                         
 
    for j in range(0,len(encode)-2):           
 
      if encode[j:j+2]==string2[i][1]:        
        #print j,
        index2.append([])
        index2[count].append(j)            
        indexcount=indexcount+1                
 
    print '\n index :',
    print index2[count]                       
    print '\n'
    cha.append([])
 
    for i in range(0,indexcount-1):
      for j in range(i+1,indexcount):
        cha[count].append(index2[count][j]-index2[count][i])
 
    #print cha[count]
    gcd2.append([])
    maybe=indexcount
 
    if indexcount>6:
      maybe=6
 
    for i in range(0,factorial(maybe-1)-1):
      for j in range(i+1,factorial(maybe-1)):
        gcd2[count].append(getGcd(cha[count][i],cha[count][j]))
 
    gcd_frequency=Counter(gcd2[count]).most_common(6)
    for i in range(0,6):
      print "frequency :{} , gcd : {}".format(gcd_frequency[i][1],gcd_frequency[i][0]) 
 
    print '\n'
    count=count+1
 
print '====================================================================================================================='
print '\n   Three letters\n'
print "====================================================================================================================="
print '\n'
 
string3=[]
 
for i in range(1,27):
   for j in range(1,27):
      for k in range(1,27):
         s=alphabetDict[i]+alphabetDict[j]+alphabetDict[k]
         string3.append([encode.count(s),s])
 
index3=[]         
count=0
cha3=[]
gcd3=[]
string3.sort(reverse=True)
 
for i in range(0,26*26*26):
  indexcount=0
  if string3[i][0]>7:   
    print '---------------------------------------------------------------------------------------------------------------------\n'           
    print " string : \"{}\", frequency : {}".format(string3[i][1],string3[i][0])          
 
    for j in range(0,len(encode)-3):
      if encode[j:j+3]==string3[i][1]:
        #print j,
        index3.append([])
        index3[count].append(j)
        indexcount=indexcount+1
 
    print '\n index : ',
    print index3[count]
    print '\n'
    #print indexcount
    cha3.append([])
 
    for i in range(0,indexcount-1):
      for j in range(i+1,indexcount):
        cha3[count].append(index3[count][j]-index3[count][i])
 
    #print cha3[count]
    gcd3.append([])
    maybe=indexcount
    if indexcount>5:
      maybe=5
 
    for i in range(0,factorial(maybe-1)-1):
      for j in range(i+1,factorial(maybe-1)):
        gcd3[count].append(getGcd(cha3[count][i],cha3[count][j]))
 
    #print gcd3[count]
    gcd_frequency=Counter(gcd3[count]).most_common(6)
 
    for i in range(0,6):
      print "frequency :{} , gcd : {}".format(gcd_frequency[i][1],gcd_frequency[i][0]) 
 
    print '\n'
    count=count+1
 
 
print '***************************************************************************************************************'
print '***************************************************************************************************************'
print '\n'
print '  Through the frequency of the gcd values for difference of each index value, we can guess the key length!\n\n'
keylength=raw_input('  Input the value as you think of as the key length : ')
print '\n'
print '###############################################################################################################'
print '###############################################################################################################'
 
encode=list(encode)
keylength=int(keylength)
 
many=[]
 
for i in range(0,keylength):
  many.append([])
 
for i in range(0,len(encode)):
  many[i%keylength].append(encode[i])
 
#print many
 
key=""
 
split_alphabet_frequency=[]
for i in range(0,keylength):
  split_alphabet_frequency.append([])                                    
 
for i in range(0,keylength):
  for j in range(1,27):                                               
    a=alphabetDict[j]    
    split_alphabet_frequency[i].append([many[i].count(a),a])   
 
 split_alphabet_frequency[i].sort(reverse=True)
  #print split_alphabet_frequency[i]
 
  #print split_alphabet_frequency[i][0][1]
  si=ord(split_alphabet_frequency[i][0][1])-ord('e')
 
  if si < 0:
    si=si+97+26
    key=key+chr(si)
  else:
    si=si+97
    key=key+chr(si)
 
  count=0
 
  for j in many[i]:
    zi=ord(j)-(si-97)
 
    if zi < 97:
      zi=zi+26
 
    many[i][count]=chr(zi)
    count=count+1
 
print "\n"
print "key : " + key
print "\n"
 
decode=""
 
for i in range(0,len(encode)):
  decode=decode+(many[i%keylength][i/keylength])
 
print "decode : \n" + decode
w=open('./decoded vigenere.txt','w')
w.write(decode)
w.close()

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