C++ PROG TO FIND N POINT DFT USING LINEAR TRANS. MATRIX

/*
-------------------------------------------------------------------------------------------------
 Assignment No:5
 Title: Compute N Point DFT Using linear transformation matrix.
-------------------------------------------------------------------------------------------------
*/

#include<conio.h>
#include<iostream.h>
#include<math.h>

# define max 50

void main()
{
  int i,j,k,n,ch,xr[max]={0},xi[max]={0};
  int x[max]={0},wi[max]={0},wr[max]={0},c[max][max]={0},s[max][max]={0};
  clrscr();
  do
  {
    cout<<"\n--::MENU::---\n";
    cout<<"\n-------------\n";
    cout<<"\n 1.DFT \n";
    cout<<"\n 2.IDFT \n";
    cout<<"\n-------------";
    cout<<"\nEnter your choice:\n";
    cin>>ch;
    switch(ch)
    {
      case 1:
          cout<<"\n Enter your choice of seq u want:";
          cin>>n;
          cout<<"\n Enter values in x(n)\n";
          for(i=0;i<n;i++)
          {
        cout<<"x("<<i<<")=";
        cin>>x[i];
          }
          for(i=0;i<n;i++)
          {
         for(j=0;j<n;j++)
         {
          c[i][j]=s[i][j]=0;
         }
          }
         for(i=0;i<n;i++)
           {
         for(j=0;j<n;j++)
        {
           c[i][j]=cos((2*M_PI*i*j)/n);
           s[i][j]=sin((2*M_PI*i*j)/n);
           s[i][j]=s[i][j]*(-1);
           cout<<c[i][j]<<"+j("<<s[i][j]<<")\t";
        }
          cout<<"\n";
        }
           for(i=0;i<n;i++)
           {
         for(j=0;j<n;j++)
          {
            wr[i]=wr[i]+(c[i][j]*x[j]);
            wi[i]=wi[i]+(s[i][j]*x[j]);
          }
         cout<<"\n";
           }
           cout<<"\nFinal Output Sequence:\n";
           for(i=0;i<n;i++)
           {
            cout<<"\t"<<wr[i]<<"+j("<<wi[i]<<")\n";
           }
           cout<<"\nFinal output Sequence is:\n";
           cout<<"{";
           for(i=0;i<n;i++)
           {
            cout<<wr[i]<<"+j("<<wi[i]<<"),";
           }
           cout<<"}";
           break;
       case 2:
          cout<<"\n Enter your choice of seq u want:";
          cin>>n;
          cout<<"\n Enter values in x(n)\n";
          for(i=0;i<n;i++)
          {
        cout<<"x("<<i<<")=";
        cin>>xr[i]>>xi[i];
          }
          for(i=0;i<n;i++)
          {
         for(j=0;j<n;j++)
         {
          c[i][j]=s[i][j]=0;
         }
          }
         for(i=0;i<n;i++)
           {
         for(j=0;j<n;j++)
          {
           c[i][j]=cos((2*M_PI*i*j)/n);
           s[i][j]=sin((2*M_PI*i*j)/n);
           s[i][j]=s[i][j]*(1);
           cout<<c[i][j]<<"+j("<<s[i][j]<<")\t";
           }
          cout<<"\n";
        }
         for(i=0;i<n;i++)
         {
        wi[i]=wr[i];
         }
         for(i=0;i<n;i++)
          {
        for(j=0;j<n;j++)
         {
            wr[i]=wr[i]+(c[i][j]*xr[j])-(s[i][j]*xi[i]);
            wi[i]=wi[i]+(s[i][j]*xr[j])+(c[i][j]*xi[j]);
         }
         wr[i]=wr[i]/n;
         wi[i]=wi[i]/n;
         cout<<"\n";
          }
           cout<<"\nFinal Output Sequence:\n";
           for(i=0;i<n;i++)
           {
            cout<<"\t"<<wr[i]<<"+j("<<wi[i]<<")\n";
           }
           cout<<"\nFinal output Sequence is:\n";
           cout<<"{";
           for(i=0;i<n;i++)
           {
            cout<<wr[i]<<"+j("<<wi[i]<<"),";
           }
           cout<<"}";
           cout<<"\n";
           break;
    }//case
  }while(ch!=3);
  getch();
}