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

float sa,x,y;

void koch(int n, float ang, float leng);

void linetheta(float ang,float l,float *x, float *y) {
 float rad=3.14159/180, k1, k2;
 k1=l*cos(rad*ang); k2=l*sin(rad*ang); *x+=k1; *y+=k2; lineto(*x,*y);
 delay(200);
}

void main() {
int    Driver, Mode, k;   /* The Graphics device driver           */
struct point { int x,y; } p1;
float  rr;

  p1.x=100, p1.y=200; rr=4; k=4;

  Driver = DETECT;                 /* Request auto-detection       */
  initgraph( &Driver, &Mode, "" );
  sa=0; setcolor(14); x=p1.x; y=p1.y; moveto(x,y); koch(k,sa,rr);
  getche(); closegraph(); /* Return the system to text mode       */
}

void koch(int n, float ang, float leng) {
  if (n == 0)  linetheta(ang,leng,&x,&y);
  else {
    koch(n-1,sa,leng); sa=fmod(sa+60,360);
    koch(n-1,sa,leng); sa=fmod(sa-120,360);
    koch(n-1,sa,leng); sa=fmod(sa+60,360);
    koch(n-1,sa,leng);
  }
}