This is my source : I think everything is correct!!!

#include <fstream.h>
#include <stdlib.h>
#include <math.h>
#include <iomanip.h>

  struct TPoint
    {double x, y;};

  struct TAngle
    {
      double ang;
      int ind;
    };

  TPoint A[5100];
  TAngle B[5100];
  int n;
  double min;
  int ind;
  TPoint tmp;

  void ReadData ()
    {
      cin >> n;
      for (int i = 0; i <= n - 1; i++)
        {cin >> A[i].x >> A[i].y;}
    }

  double dist (TPoint const &a, TPoint const &b)
    {return sqrt((a.x - b.x)*(a.x - b.x) + (a.y - b.y)*(a.y - b.y));}

  int comp (const void *e1, const void *e2)
    {
      double z = ((TAngle*)e1)->ang - ((TAngle*)e2)->ang;
      if (z < 0)
        return -1;
      if (z > 0)
        return 1;
      if (z == 0)
        while (1) // Here if there is four points on one circle
program gets TL...
          {}
    }

  void Solve ()
    {
      min = A[0].y;
      ind = 0;
      for (int i = 1; i <= n - 1; i++)
        if (A[i].y < min)
          {
            min = A[i].y;
            ind = i;
          }
      tmp = A[0];
      A[0] = A[ind];
      A[ind] = tmp;
      min = atan2 (A[1].y - A[0].y, A[1].x - A[0].x)*1000;
      ind = 1;
      for (int i = 2; i <= n - 1; i++)
        if (atan2 (A[i].y - A[0].y, A[i].x - A[0].x)*1000 < min)
          {
            min = atan2 (A[i].y - A[0].y, A[i].x - A[0].x)*1000;
            ind = i;
          }
      tmp = A[1];
      A[1] = A[ind];
      A[ind] = tmp;
      double a, b, c;
      for (int i = 2; i <= n - 1; i++)
        {
          B[i].ind = i;
          a = dist (A[0], A[i]);
          b = dist (A[1], A[i]);
          c = dist (A[0], A[1]);
          B[i].ang = acos ((a*a + b*b - c*c)/(2*a*b));
          B[i].ang *= 1000;
        }
      qsort (&B[2], n - 2, sizeof (TAngle), comp);
    }

  void WriteData ()
    {
      cout << setiosflags (ios::fixed) << setprecision (0) << A[0].x
<< " " << A[0].y << endl;
      cout << setiosflags (ios::fixed) << setprecision (0) << A[1].x
<< " " << A[1].y << endl;
      cout << setiosflags (ios::fixed) << setprecision (0) << A[B[(1
+ n)/2].ind].x << " " << A[B[(1 + n)/2].ind].y << endl;
    }

  int main ()
    {
      ReadData ();
      Solve ();
      WriteData ();
      return 0;
    }

how you find testdata?????

when i sort points i add to my source while (1) {} if there is four
point on one circle so my program to get TL. And it gets it... so
there is test case where there is four points on one circle ...

Maybe your program really works very slow, better use MLE or some Crash to find incorrect tests.

Those you can emulate MLE:
Procedure MakeMLE;
 Begin
  MakeMLE;
 End;

Those you can emulate OLE:
Procedure MakeOLE;
 Begin
  While True Do WriteLn;
 End;