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*echo* *echo*
Topic Started: Apr 2 2008, 11:51 AM (237 Views)
s3c
Just registered
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forum's been kinda dead lately... monoalphabetic multilateral, really easy, any takers?

15243132541253414532125341234514532125341425314325132451325414325152341524315234
15423132541253414253213451432515324124531342512534213451432515324145321253412453
12534123451245315243132541253414532125341523414253143251234512543152431253414532
13542134251254312534143521253414325143521354212534154231325414325124351354212345
13425142351524313254125342134512435123451425315234125341253413245132541432515234
15243152341234514532125341345215324152341524313542143251432513524134251425313245
12543143251453212345152431524312534142531524313425143251425314352125341432514352
13542125341542313254143251235412534135421342512534153421253413425142531453212534
13425142531243512345145321425312345152431342514325142531234514532125341345215324
15234152431435214325152341524314352143251425313425142531324515243132541253413425
14532135421342515342125341523412435132541532412435135241435212345135421234513254
14253134251532413524
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Paarth Dave
Advanced Member
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I am an amateur in cryptography....
Please explain to me what do you mean by monoalphabetic multilateral???

Cryptography Vanquished....
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Revelation
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It means that it is just a simple monoalphabetic substitution cipher but that every letter is represented by an array of letters.

If you look at this text, you'll notice that there are 5 different symbols. This means that you need 5 or more characters to reprensent the alphabet (5 *5 = 25). My guess is that indeed 5 characters are used and that one letter of the alphabet is not in the text.
RRRREJMEEEEEPVKLWENFNVJKEEEEEAOLKAFKLXCFZAASDJXZTTTTTTTLSIOWJXMOKLAFJNNKFNXN
RAGRBAQEMHIGDJVDSEOXVIYCELFHWLELJFIENXLRATALSJFSLCYTKLASJDKMHGOVOKAJDNMNUITN
RRRRLJVEEEEECLYVYHNVPFTAEEEEEMWLMEIRNGLARWJAKJDFLWNTIERJMIPQWOTZEOCXKNUBNXCN
RJIRPOWEANFUSNCZVDVZNMSFEKLOEPZLDKDJWSAAAAAAAOERHJCTNCKFRIMVKSOFOMKMANREWNBN
RZUDRGXEEEEENFQIDVLQNCKNEEEEEDGLLLLLLAWIOSNCDARLODMTOEJXMILDFJROTKJSDNLVCZNN
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Paarth Dave
Advanced Member
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Thanks buddy

Cryptography Vanquished....
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Okay, I wrote a nice little program to convert this into a more workable form:

Code:
 

#include "stdafx.h"
#include <string.h>

#define NUMBOFINTSFORONECHAR 5

struct NUMBANDALPHA
{
char numbseq[NUMBOFINTSFORONECHAR]; // number sequence
char alpha; // alphabetic representative
};

int _tmain(int argc, _TCHAR* argv[])
{
char buffer[1000];
NUMBANDALPHA sequences[200];
char finalstring[200];

char newalphachar = 'A';
int seqlength = 0;
int finstringpos = 0;

FILE* a = fopen("cipher.txt", "rt");

if (!a)
 return 1;

int bufpos = 0;
while(!feof(a)) // read the file
{
 char ch = getc(a);
 if (ch >= '0' && ch <= '9') // only numbers
 {
  buffer[bufpos] = ch;
  bufpos++;
 }
}
buffer[bufpos] = 0;

fclose(a);

if (bufpos %  NUMBOFINTSFORONECHAR != 0)
{
 printf("Error: this number is wrong.\n");
 return 2;
}

for (int i = 0; i < bufpos; i += NUMBOFINTSFORONECHAR) // convert to alpha
{
 char curseq[NUMBOFINTSFORONECHAR];
 strncpy(curseq, buffer + i, NUMBOFINTSFORONECHAR);

 bool found = false;
 for (int j = 0; j < seqlength; j++) // check if the sequence already exists
 {
  if (strncmp(curseq, sequences[j].numbseq, NUMBOFINTSFORONECHAR) == 0)
  {
   finalstring[finstringpos] = sequences[j].alpha;
   finstringpos++;
   found = true;
   break;
  }
 }

 if (!found)// a new sequence is found, generate a new ascii value
 {
  strncpy(sequences[seqlength].numbseq, curseq, NUMBOFINTSFORONECHAR);
  sequences[seqlength].alpha = newalphachar;
  newalphachar++;
 
  finalstring[finstringpos] = sequences[seqlength].alpha;
  finstringpos++;
  seqlength++;
 }
}

finalstring[finstringpos] = 0;
printf(finalstring);

FILE * b = fopen("output.txt", "wt");
fprintf(b, finalstring);
fclose(b);

getchar();
return 0;
}



These are my results(hidden)
ABCDCEDCFGHBGIAIJBCFKGLMNCKGLDCMCEMABCDCIFGEOACDPNOCQCGQPCJBGRPENSABCKREFICCHBGIAIEDCTLIAPGGUNFHOGDEAACFANGFQCGQPCJBGVCPNCWCNFDCNFREDFEANGFEDCTLIAQGIAQGFNFHABCNDPNWCIRBLRUQEPEBFNLU

Now it's a nice mono sub :)
RRRREJMEEEEEPVKLWENFNVJKEEEEEAOLKAFKLXCFZAASDJXZTTTTTTTLSIOWJXMOKLAFJNNKFNXN
RAGRBAQEMHIGDJVDSEOXVIYCELFHWLELJFIENXLRATALSJFSLCYTKLASJDKMHGOVOKAJDNMNUITN
RRRRLJVEEEEECLYVYHNVPFTAEEEEEMWLMEIRNGLARWJAKJDFLWNTIERJMIPQWOTZEOCXKNUBNXCN
RJIRPOWEANFUSNCZVDVZNMSFEKLOEPZLDKDJWSAAAAAAAOERHJCTNCKFRIMVKSOFOMKMANREWNBN
RZUDRGXEEEEENFQIDVLQNCKNEEEEEDGLLLLLLAWIOSNCDARLODMTOEJXMILDFJROTKJSDNLVCZNN
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jdege
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Isn't that supposed to be "multiliteral"?
When cryptography is outlawed, bayl bhgynjf jvyy unir cevinpl.
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s3c
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jdege
Apr 3 2008, 12:19 PM
Isn't that supposed to be "multiliteral"?

ahh, jip it is, thnx for the spot
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