Write a C Program to Draw Ellipse using graphics

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

SOURCE CODE : :

/*  C Program to Draw Ellipse using graphics  */

#include<graphics.h>
#include<conio.h>
#include<stdio.h>
void plotpoints(int cx, int cy, int x, int y) {
        putpixel(cx + x, cy + y, 4);
        putpixel(cx - x, cy + y, 4);
        putpixel(cx + x, cy - y, 4);
        putpixel(cx - x, cy - y, 4);
}
void main() {
        int cx, cy, rx, ry;
        printf("Enter the center ");
        scanf("%d%d", &cx, &cy);
        printf("x radius : ");
        scanf("%d", &rx);
        printf("y radius : ");
        scanf("%d", &ry);
        long rx2 = (long) rx * rx;
        long ry2 = (long) ry * ry;
        long trx2 = 2 * rx2;
        long try2 = 2 * ry2;
        long p, x = 0, y = ry;
        long px = 0;
        long py = trx2 * y;
        p = (long) ((ry2 - (rx2 * ry) + (0.25 * rx2)) + 0.5);
        int gd = DETECT, gm = DETECT;
        initgraph(&gd, &gm, "");
        cleardevice();
        putpixel(cx, cy, 15);
        while (px < py) {
                plotpoints(cx, cy, x, y);
                x++;
                px += try2;
                if (p < 0)
                            p += ry2 + px; else {
                        y--;
                        py -= trx2;
                        p += ry2 + px - py;
                }
        }
        py = trx2 * y;
        px = try2 * x;
        p = (long) ((ry2 * (x + 0.5) * (x + 0.5) + rx2 * (y - 1) * (y - 1) - rx2 * ry2) + 0.5);
        while (y >= 0) {
                plotpoints(cx, cy, x, y);
                y--;
                py -= trx2;
                if (p > 0)
                            p += rx2 - py; else {
                        x++;
                        px += try2;
                        p += rx2 - py + px;
                }
        }
        getch();
}

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