程序代码：

#include "graphics.h"
#define closegr closegraph

void initgr(void)
{
  int gd = DETECT, gm = 0;
  registerbgidriver(EGAVGA_driver);
  initgraph(&gd, &gm, "");
}

int main(void)
{
  void func(int xend,int cut,int sure);
  initgr(); /* BGI初始化 */
  outtext("Please wait...");
  sleep(2);
  while (1)
  {
    func(10,200,1);
    func(9,0,-1);
  }
  getch();
  closegr();
  return 0;
}


void func(int xend,int cut,int sure)
{
  int i,fo,xnow,xnowb;
  for (i=-xend;i<=xend;i++)
  {
    if (kbhit()) exit(1);
    setcolor(i%15+1);
    xnow=cut-sure*(i*i+1);
    rectangle(xnow*3,300,xnow*3+30,350);
    setfillstyle(1,i%15+1);
    floodfill(xnow*3+1,300+1,i%15+1);
    xnowb=i+20;
    rectangle(300,xnowb*15,330,xnowb*15+28);
    floodfill(300+1,xnowb*15+1,i%15+1);
    for (fo=0;fo<=1000;fo++) {delay(5);}
    printf("\n\n");
  }
}