static void Main(string[] args)
{
qgr qgr = new qgr();
char[] cipherText = "YCAHFUECQIYSAYAQVYOXAYYOCGOHXKDTQXCXSOWSXKXFTBPRFDVDUOYXUDNAIXFQUDIRSOBGYIUTAYMDVOYVSOTBPRFDRSXTTDVUHTXQHAXFFBCYPQUHBUDNNFMDEBGSUMZNQIOHCDNDYIDYOYHCQFYZDYDHUTAVYAHTHCFNAXBKQNAGDNYUCQUTSQORBFKCUMVNOYULDMMAKUUKYRXSGSDATDRSFEXUEXRHFNUDYOXKXRRSYIQURFDYNRYARYANFQGOCXUDEGFUXFYRSTGBVAHCFXORHCKUDICHAQHCKPYCRCUDGMZLDANRYACYUKQNSODAXEBRLQMDYNXFDMGNYOXUXLECFQYXHCXEFBIXAVFDUBRSXTTDRSOHBQNGSOTBPRFDGBUBDZZEQUPXTBPRFDBUDNNFMDEBBHAVFDENECCZYIUDDZPFGUXEBTLQHVORRCSOOYKRGBMSGBHRSUROYNXUDFDYDYIDRYYOPKGSBFCIQFFUZYYIULQAXFRSXTTDYAKUYARYNXOYHCFNUDNKTAEABGYIFDIDBZYGSOXCSOUKRSXTTDULDYWGCYECEBYNFXSDLNHRSOFIMXYQDNQXXKZDYDOHTDZGHCUDXUXBUKOYDAXFOHCGPZKURSECCIFNCDZYYITBPRFDBUITAVFDXQDPZCKUATBSULQAXFNDBUEUMUADCYYIOYHCKUDRQFBTORYBGPKXOMXEZBLQYAOXQATDSOYAOVSOEGSVTSVHAYCDPQTBPRFDYCSFLNHCFUGHFNNPBCQPFXYUPEBQYCQFGNYOEGSVTSVHUTAQTBAXUKDCANNGPKECFLYUKSSVOYMAYZKUZEOXXQXFNAIXFQPQXDUYYAOQFXITFQPQTAQDSOTBPRFDBGXRAVFDPQTDBCQPFXYACYEXHAUYBFQIVSBEIAXNHTXQCFIODFASBVFQIADOECQCTSUKAOHTOYGUUDGFYUABTBPRFDBUDNNFMDEBAGYOXKMSBHFQDAQINPNFXHXKDZMXKUBGUYHCORXKMSAKFBHTXQCDYIPQXDUYNAHAFQITAVFDKSSVUBZYBGICIQSBDYIHUYLDNFIXLNYXXKZEUDZGHCQPFXGVATNRNFMDEBUHUWSQFNYORBYXQPXPMAYZLXAVFDXKPAHTXQXFNAYNFXCGBAXFORCRAVFDCGAWOBRORCFXNZZEDYIDYNDIDUYXQITBPRFDAORQATXODUXQQIPXYCXKAMFNBFOBYUXCKUCYUBXUFPFNOYXKDACGFMYOVYBXAVFDRSXTTDTBPRFDNFMDEBBHUYCYPNFNTBPRFDZGECKZBDHCFXQEATVYAXNSDANRYAHTHCFXKXUBULXPBFYCCQLXRSYILNYXXKDAADYIFPXPHOKSORNGSOPFUDBUDNRSXTTDORUYXLYACYHCSOWSRVDMQNKPUBYSDYYHBTAVFUYNROLQPFOIBGNFBFUYDSEUMUCDCYUYRBYXYAYCTBPRFDBUDNXKOHDBXQHAQFITAVFDFDNFNQZGECFQUEFBDYYAHTHCFNAXBKQNBHAVFDKSSTDMCZOHXPFNOYBFQBQRCGGKYCCKUTSQBSEAHTXQCDIXAVMXKXXPBGUYUYHCLNARBRKUTBPRFDNBPVFNUBBFSOYMBYXLBHXFLXXKIRAVFDXSXTTDNERSXTTDQBSQFNBFFBTANPYRXKTAAVULQAXFXFBFZLDYYHXKQYZBKXDMGBBOFNRAAVNFMDEBUHUWBTLQHVORRCYAOTBNXQCDWSHRAVFDPKXFUVFXORDYYHSUPQTDCYWSHORCFNBELXAVFDBUDNNFMDEBBHAVFDYUNRNDYIORCGGKORRCUDYRBXLGYIYCAUHLDYOYCGGKBDOHTBORYAHVFUXFORXQPVCYYIOYCYPFVYAXNFMUXHAXQETAVRXKTSOBKPYCTGSOARDFZCGONDBUEUMUCDCYUYTBPRFDRSXTTDHCOBHCLXRSAFACFUHGHCFPAVXPOVSOBFKCFUMRATBUEQOVYAHCQXAXPXYRYOXKNAHAFQGOTBPRFDPKECCBAVFDDAKPFUECEZBRLQMDYNXFDMVOSYUYUYQUQRXKFDGUPKXFGRDZYAXOIXFQPQXDUYMSUHOHZCKBROCDYIUMMUECFQMDHTHCLUBENKDYNFMDEBUHGKBDOHTBORVUHLQXYAXVFXRSWUPKGSSOFIMSYCSOHODNLNYXXKRSECCBAVFDNFMDEBBHAVFDPAAFAXFNXKOHDBYAHOXKBCFUCFDQQFHTHCORYCVSBEIAQXBRCQKUAKATHCFPOYXFFDDYHCFXUTAVKSZCKXDATDUDYRXKNAHAFQGOXURCUDNKIFYQDYIHAVFDVUUHBGICVOFUARBERDXFPKECKBYAHTHCFXKUYUPXFNTBPRFDRSXTTDPAHTXQXFIRAVFDAOXOIXFQPQXDUYFDNFUDDQAXHCFXXUZEUDORYBPNPUPXXLUHBUTDOIBUGDYIQBANQITBPRFDPKECCBAVFDHCGBGBYSAYOILXAVFDHCXPTBPRFDASGNYOXKGKNPWSGBCDWSROAFNEMSAMOYGSSFKXDATDGSUDIRAVFDAOROHTHCQFUBRVAVXPHOXUFPFNNPUAFQOYRDXLYCTBPRFDUDMFFXQFITQBUKGRGBLDOHUDIAKNUDGKDYIDYIYCAUHLMSAMUDMRATMSAMCZLQDFQXTAYUPF".ToArray();
char[] plainText = new char[cipherText.Length];
char[] key = "RXTHCAUOSBDNYGIMPVWZFEQKL".ToArray();
int i = 0;
double score, maxscore = -99e99;
while (true)
{
Console.WriteLine("Beginning iteration");
i++;
score = playfairCrack(cipherText, ref key);
if(score > maxscore)
{
maxscore = score;
Console.WriteLine("best score so far: " + score);
Console.WriteLine("Iteration: " + i);
Console.Write("Key: '");
for (int j = 0; j < key.Length; j++)
{
Console.Write(key[j]);
}
Console.WriteLine("\n");
plainText = playfairDecipher(key, cipherText);
Console.Write("plaintext: '");
for (int j = 0; j < plainText.Length; j++)
{
Console.Write(plainText[j]);
}
Console.Write("'\n");
}
}
}
private static float playfairCrack(char[] text, ref char[] key)
{
qgr qgr = new qgr();
Random rand = new Random();
float bestScore = 0F;
char[] deciphered;
char[] testKey = key;
char[] maxKey = key;
double prob, dF, maxScore, score;
deciphered = playfairDecipher(testKey, text);
maxScore = qgr.scoreTextQgram(deciphered);
bestScore = (float)maxScore;
for (float T = 20; T >= 0; T -= 0.2F)
{
for (int count = 0; count < 5000; count++)
{
testKey = modifyKey(maxKey);
deciphered = playfairDecipher(testKey, text);
score = qgr.scoreTextQgram(deciphered);
dF = score - maxScore;
if(dF >= 0)
{
maxScore = score;
testKey = maxKey;
}
else if (T > 0)
{
prob = Math.Exp(dF / T);
if (prob > 1.0 * rand.Next() / 2147483647)
{
maxScore = score;
testKey = maxKey;
}
}
if(maxScore > bestScore)
{
bestScore = (float)maxScore;
key = maxKey;
}
}
}
return bestScore;
}
