#include <graphics.h>
#include <conio.h>

main () {
   initgraph(VGA, VGAHI, "g:\\tc\\bgi");
   line(0, 0, 639, 0);
   line(0,0,0,479);
   getch();
   setviewport(50,0,200,50,1);
   clearviewport();
   getch();
   line(0,10,639,10);
   line(10,0,10,400);
   getch();
   closegraph();
}