Bresenham's Circle Drawing Algorithm

#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<ll,ll>pll;
#define fastread() (ios_base:: sync_with_stdio(false),cin.tie(NULL));
#define eb emplace_back
#define F first
#define S second
int main()
{

   fastread();

   ll i,j,n,m,p,a,sum=0,k,t,b,c,d,cnt=0,q,l,r,ans=0;

      bool flag=false;


      ll xc,yc,x,y;


      string str;

      cout<<"Input the radius r and center x,y"<<endl;

      cin>>r>>xc>>yc;

       x=0,y=r;

       d=(3-(2*r));

      cout<<"\nIteration No(i) : (Xi,Yi)  di   (Xi+1,Yi+1)"<<endl;

  i=1;

  vector<pll>v;

  v.eb(x,y);

      while(x<y)
      {


           cout<<i<<"  ("<<x<<","<<y<<") "<<d<<" (";

           if(d<0)
           {
               d=d+(4*x)+6;
               x++;

           }
           else{

                d=d+4*(x-y)+10;


            x++;
            y--;
           }

           cout<<x<<","<<y<<") "<<endl;

           v.eb(x,y);

           i++;


      }

      cout<<"\nXc : "<<xc<<",Yc:"<<yc<<endl;

      cout<<"( x, y) ";

      for(auto x : v)
      {
          cout<<"( "<<x.F<<","<<x.S<<") ";
      }

      cout<<endl<<endl;

       cout<<"( x+"<<xc<<",y+"<<yc<<") ";

      for(auto x : v)
      {
          cout<<"( "<<x.F+xc<<","<<x.S+yc<<") ";
      }

      cout<<endl<<endl;



       cout<<"( -x+"<<xc<<",y+"<<yc<<") ";

      for(auto x : v)
      {
          cout<<"( "<<-x.F+xc<<","<<x.S+yc<<") ";
      }

      cout<<endl<<endl;


         cout<<"( x+"<<xc<<",-y+"<<yc<<") ";

      for(auto x : v)
      {
          cout<<"( "<<x.F+xc<<","<<-x.S+yc<<") ";
      }

      cout<<endl<<endl;

         cout<<"( -x+"<<xc<<",-y+"<<yc<<") ";

      for(auto x : v)
      {
          cout<<"( "<<-x.F+xc<<","<<-x.S+yc<<") ";
      }

      cout<<endl<<endl;

         cout<<"( y+"<<xc<<",x+"<<yc<<") ";

      for(auto x : v)
      {
          cout<<"( "<<x.S+xc<<","<<x.F+yc<<") ";
      }

      cout<<endl<<endl;


       cout<<"( y+"<<xc<<",-x+"<<yc<<") ";

      for(auto x : v)
      {
          cout<<"( "<<x.S+xc<<","<<-x.F+yc<<") ";
      }

      cout<<endl<<endl;


         cout<<"( -y+"<<xc<<",x+"<<yc<<") ";

      for(auto x : v)
      {
          cout<<"( "<<-x.S+xc<<","<<x.F+yc<<") ";
      }

      cout<<endl<<endl;

         cout<<"( -y+"<<xc<<",-x+"<<yc<<") ";

      for(auto x : v)
      {
          cout<<"( "<<-x.S+xc<<","<<-x.F+yc<<") ";
      }

      cout<<endl;












      return 0;


}