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

float sa,x,y;

void koch(int, float, float);
void linetheta(float ang,int l,float *x, float *y) {
 float rad=3.14159/180, k1, k2;
 k1=l*cos(rad*ang); k2=l*sin(rad*ang);
 line(*x,*y,*x+k1,*y+k2); *x+=k1; *y+=k2; delay(70);
}

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

  p1.x=150, p1.y=300; rr=4; k=4;

  Driver = DETECT;                 /* Request auto-detection       */
  initgraph( &Driver, &Mode, "" ); j=12;
  sa=0; setcolor(j++); x=p1.x; y=p1.y; moveto(x,y);

  for (i=0; i<3; i++) {
    koch(k,sa,rr); sa=fmod(sa-120,360); getche(); setcolor(j++);
  }

  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);
  }
}