C Program to implement Boundary Fill Algorithm

#include<stdio.h>
#include<conio.h>
#include<graphics.h>
#include<dos.h>



void fill_right(x,y)
int x , y ;
{
if((getpixel(x,y) != WHITE)&&(getpixel(x,y) != RED))
{
putpixel(x,y,RED);
fill_right(++x,y);
x = x - 1 ;
fill_right(x,y-1);
fill_right(x,y+1);
}
delay(1);
}


void fill_left(x,y)
int x , y ;
{
if((getpixel(x,y) != WHITE)&&(getpixel(x,y) != RED))
{
putpixel(x,y,RED);

fill_left(--x,y);
x = x + 1 ;
fill_left(x,y-1);
fill_left(x,y+1);
}
delay(1);
}


void main()
{
int x,y,n,i;
int gd=DETECT,gm;
clrscr();

initgraph(&gd,&gm,"c:\\tc\\bgi");



/*- draw object -*/

line (50,50,200,50);
line (200,50,200,300);
line (200,300,50,300);
line (50,300,50,50);

/*- set seed point -*/
x = 100; y = 100;

fill_right(x,y);
fill_left(x-1,y);

getch();
}