Desenare cerc si poligon in C

>Desenare cerc si poligon in C, marire/micsorare si mutare.

#include <graphics.h>
#include <stdlib.h>
#include <stdio.h>
#include <conio.h>
#include <iostream.h>
#include <math.h>
#include <dos.h>
int pi=M_PI;

int main(void)
{
   int gdriver = DETECT, gmode, errorcode;
   int xmax, ymax,y,x,raza,poly[20],a,b,cemut,ind;
   char ch;
   initgraph(&gdriver, &gmode, "");
   errorcode = graphresult();
   if (errorcode != grOk)
    {
      printf("Graphics error: %sn", grapherrormsg(errorcode));
      printf("Press any key to halt:");
      getch();
      exit(1);
    }
   xmax = getmaxx();  ymax = getmaxy();
/*
  for(int i=0;i<=xmax/2;i++)
   {
   outtextxy(0,0,"Resizing a circle");
    circle(xmax/2,ymax/2,i);
    delay(10);
    cleardevice();
   }

 for(i=-220;i<=xmax+220;i++)
   {
   outtextxy(0,0,"Moving a circle on X axes");
    circle(i,ymax/2,200);
    delay(3);
    cleardevice();
   }
   for(i=-220;i<=xmax+220;i++)
   {
   outtextxy(0,0,"Moving a circle on Y axes");
   setfillstyle(SOLID_FILL,5);
    circle(xmax/2,i,200);
    delay(3);
    cleardevice();
   }
 */
 x=xmax/2;     y=ymax/2;     raza=200;
  a=0;b=0;    cemut=1;  ind=1;
do
{
  //50,52,54,56.58
    ch=getch();
    cleardevice();
    //cout<<ch;
    if(ch=='c') cemut=1;
    if(ch=='d') cemut=2;
    if(ch=='a') cemut=3;
    if(ch=='v') ind++;
    if(ch=='b') ind--;
    if(ch=='P') { y=y+ind; b=b+ind;}  //in jos
    if(ch=='H') { y=y-ind; b=b-ind;} // in sus
    if(ch=='M') { x=x+ind; a=a+ind;} //  drepta
    if(ch=='K') { x=x-ind; a=a-ind;} //  stanga
    if(ch=='+') raza++;
    if(ch=='-') raza--;
if(cemut==1 || cemut==3)    circle(x,y,raza);
    //drawpoly(4,xmax/4,ymax/4,3*xmax/4,3*ymax/4);
   poly[0] = xmax/4+a;        /* 1st vertext */
   poly[1] = ymax/4+b;

   poly[2] = 3*xmax/4+a; /* 2nd */
   poly[3] = ymax/4+b;

   poly[4] = 3*xmax/4+a; /* 3rd */
   poly[5] = 3*ymax/4+b;

   poly[6] = xmax/4+a;  /* 4th */
   poly[7] = 3*ymax/4+b;
/*
   drawpoly doesn't automatically close
   the polygon, so we close it.
*/
   poly[8] = poly[0];
   poly[9] = poly[1];

   /* draw the polygon */
if(cemut==2 || cemut==3)  drawpoly(5, poly);
}
 while(ch!=27);
   getch();
   closegraph();
   clrscr();
   return 0;
}