I need help to decrypt string

[fyue]

I need help

c+ string decryption algorithm switch to au3

str = '65666760666666166265666462656765661567616715626564156265676266646766626567626767666A666B6662626566646667666A6760676162656715666A6760626B62656515666A67606262676766606265661067606766676162656664666B666A67616616666067676265676766646761626B62656566666A62656612666A666B6662626B62656515666A67606265666A666B661267156265661666646763666062656715666A67606767676666606612666362656761666A626566676612666466116660626B116460666262156B712949EF'



1.1 
Behind the 8-byte string and do the following calculation of the remaining bytes, respectively, were obtained 4-byte DWORD and (strlen-8) / 2-byte sequence
i = 0;
while (i < strlen){
if (str[i] > 0x39){
  dst[i/2] = (str[i]-7) << 4;
}else{
  dst[i/2] = str[i] << 4;
}

if (str[i+1] > 0x39){
  dst[i/2] = dst[i] | (str[i+1] - 0x37);
}else{
  dst[i/2] = dst[i] | (str[i+1] - 0x30);
}

i += 2;
}

Be dst4, dstmain

1.2 
  DWORD dwCode = dst4 xor 0x83ACB78D ;
  i = 0;
  while (i < dstmain.size){
   dstmain[i] = dstmain[i] XOR (dwCode[0] XOR 0xAF)
   dwCode = dwCode * 0x34F85F9;
   dwCode = ( (dwCode + dstmain.size)*dstmain.size + 0xA13292 ) * dstmain.size;
   i++;
  }

Edited April 20, 2010 by fyue