C Program
#include<graphics.h> #include<conio.h> #include<dos.h> #include<process.h> int cx=300,cy=100,r=300; int x=0,y,p; int path(int dtn) { int x1,y1; setcolor(15); if(x>=y) { return 0; } cleardevice(); if(dtn==1) { circle(cx+x,cy+y,20); line(cx,cy,cx+x,cy+y); } else { circle(cx-x,cy+y,20); line(cx,cy,cx-x,cy+y); } delay(10); if(kbhit()) exit(0); x++; if(p<0) p+=2*x+1; else { y--; p+=2*(x-y)+1; } x1=x; y1=y; path(dtn); cleardevice(); if(dtn==1) { circle(cx+x1,cy+y1,20); line(cx,cy,cx+x1,cy+y1); } else { circle(cx-x1,cy+y1,20); line(cx,cy,cx-x1,cy+y1); } delay(10); if(kbhit()) exit(0); return(0); } void main() { int gd=DETECT,gm=DETECT; initgraph(&gd,&gm,""); cleardevice(); putpixel(300,100,4); while(1) { x=0; y=r; p=1-r; path(1); x=0; y=r; p=1-r; path(0); } }