Write a C Program to perform Pendulum in graphics

Below is the source code for C Program to perform Pendulum in graphics which is successfully compiled and run on Windows System to produce desired output as shown below :

SOURCE CODE : :

/*  C Program to perform Pendulum in graphics  */

#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);
        }
}

Above is the source code for C Program to perform Pendulums in graphics which is successfully compiled and run on Windows System.The Output of the program is shown above .