using System;
using System.Windows.Forms;
using System.Drawing;
using System.Drawing.Drawing2D;
using System.Threading;
class Joonis8:Form{
  int x=10, vx=3;
  bool veel=true;
  public Joonis8(){
     Thread t=new Thread(new ThreadStart(liigu));
     t.Start();
  }
  protected override void OnPaint(PaintEventArgs e){
    base.OnPaint(e);
    Graphics g=e.Graphics;
    g.DrawEllipse(new Pen(Color.Green), x, 50, 20, 20);
  }
  void liigu(){
    while(veel){
     x+=vx;
     if(x>this.Width && vx>0){vx=-vx;}
     if(x<0 && vx<0){vx=-vx;}
     this.Invalidate();
     Thread.Sleep(70);
    }
  }
  public static void Main(string[] arg){
     Application.Run(new Joonis8());   
  }
}