/*
   Golay Code and Witt Design Generator in C++
   by Ashay Dharwadker
   http://www.dharwadker.org
   ashay@dharwadker.org
*/

#include <iostream>
#include <fstream>
#include <string>
#include <vector>
#include <algorithm>
using namespace std;

vector<bool> binary(int n);
int power(int k, int j);
vector<bool> golay(vector<bool> c);
ofstream outfile1("golay.txt");
ofstream outfile2("witt.txt");

int main()
{
 cout<<"The Golay Code and Witt Design Generator."<<endl;
 vector<vector<bool> > code;
 vector<vector<bool> > design;
 int i, j, n;
 for(n=0; n<4096; n++)
 {
  cout<<"Generating Golay Code Word Number:"<<n<<'\r';
  int weight=0;
  vector<bool> temp, word;
  temp=binary(n);
  for(i=0; i<12-temp.size(); i++)
   word.push_back(0);
  for(i=0; i<temp.size(); i++)
   word.push_back(temp[i]);
  for(i=0; i<golay(word).size(); i++)
   {
    if(golay(word)[i]) weight++;
   }
   code.push_back(golay(word));
  if(weight==8)
   design.push_back(golay(word));
 }
 cout<<"Golay code and Witt design created ..."<<endl;
 sort(code.begin(), code.end());
 sort(design.begin(), design.end());
 cout<<"Sorting complete, writing to files ..."<<endl;
 for(i=0; i<code.size(); i++)
 {
  for(j=0; j<code[i].size(); j++)
    {
     if(code[i][j]==0)
      outfile1<<"0";
     else
      outfile1<<"1";
    }
  outfile1<<endl;
 }
 for(i=0; i<design.size(); i++)
 {
  for(j=0; j<design[i].size(); j++)
    {
     if(design[i][j]==0)
      outfile2<<"0";
     else
      outfile2<<"1";
    }
  outfile2<<endl;
 }
cout<<"See golay.txt and witt.txt for results."<<endl;
system("PAUSE");
return 0;
}

vector<bool> binary(int n)
{
 vector<bool> representation;
 if(n==0) return representation;
 int i=0;
 while(power(2,i)<=n) i++;
 n=n%power(2,i);
 for(int j=i-1; j>=0; j--)
  {
    if(power(2,j)<=n)
     representation.push_back(1);
    else
     representation.push_back(0);
    n=n%power(2,j);
   }
 return representation;
}

int power(int k, int j)
{
 if(j==0) return 1;
 int p=1;
 for(int i=1; i<=j; i++)
   p*=k;
 return p;
}

vector<bool> golay(vector<bool> c)
{
 vector<bool> sum;
 sum.push_back(c[0]);
 sum.push_back(c[1]);
 sum.push_back(c[2]);
 sum.push_back(c[3]);
 sum.push_back(c[4]);
 sum.push_back(c[5]);
 sum.push_back(c[6]);
 sum.push_back(c[7]);
 sum.push_back(c[8]);
 sum.push_back(c[9]);
 sum.push_back(c[10]);
 sum.push_back(c[11]);
 sum.push_back(c[0]^c[1]^c[3]^c[4]^c[5]^c[9]^c[11]);
 sum.push_back(c[1]^c[2]^c[4]^c[5]^c[6]^c[10]^c[11]);
 sum.push_back(c[0]^c[2]^c[3]^c[5]^c[6]^c[7]^c[11]);
 sum.push_back(c[1]^c[3]^c[4]^c[6]^c[7]^c[8]^c[11]);
 sum.push_back(c[2]^c[4]^c[5]^c[7]^c[8]^c[9]^c[11]);
 sum.push_back(c[3]^c[5]^c[6]^c[8]^c[9]^c[10]^c[11]);
 sum.push_back(c[0]^c[4]^c[6]^c[7]^c[9]^c[10]^c[11]);
 sum.push_back(c[0]^c[1]^c[5]^c[7]^c[8]^c[10]^c[11]);
 sum.push_back(c[0]^c[1]^c[2]^c[6]^c[8]^c[9]^c[11]);
 sum.push_back(c[1]^c[2]^c[3]^c[7]^c[9]^c[10]^c[11]);
 sum.push_back(c[0]^c[2]^c[3]^c[4]^c[8]^c[10]^c[11]);
 sum.push_back(c[0]^c[1]^c[2]^c[3]^c[4]^c[5]^c[6]^c[7]^c[8]^c[9]^c[10]);
 swap(sum[10],sum[16]);
 swap(sum[13],sum[20]);
 swap(sum[3],sum[8]);
 swap(sum[6],sum[14]);
 swap(sum[7],sum[15]);
 return sum;
}