program line;
private
  drawn;
  fix_x=0;
  fix_y=0;
 
begin
  set_mode(320,240,16);      
  x=10; y=10;
  loop        
    if(key(_up))y--;end;
    if(key(_down))y++;end;
    if(key(_left))x--;end;
    if(key(_right))x++;end;
   
    delete_draw(drawn);
    drawing_color(-1);
    draw_line(fix_x,fix_y,x,y);
    frame;
   end;
 end;