C Program to Implement Flood Fill Algorithm

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

void fill_right(x,y)
int x , y ;
{
if(getpixel(x,y) == 0)
{
putpixel(x,y,RED);
fill_right(++x,y);
x = x - 1 ;
fill_right(x,y-1);
fill_right(x,y+1);

}
}

void fill_left(x,y)
int x , y ;
{
if(getpixel(x,y) == 0)
{
putpixel(x,y,RED);

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

}
}


void main()
{
int x , y ,a[10][10];
int gd, gm ,n,i;

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

printf("\n\n\tEnter the no. of edges of polygon : ");
scanf("%d",&n);
printf("\n\n\tEnter the cordinates of polygon :\n\n\n ");

for(i=0;i<n;i++)
{
printf("\tX%d Y%d : ",i,i);
scanf("%d %d",&a[i][0],&a[i][1]);
}

a[n][0]=a[0][0];
a[n][1]=a[0][1];

printf("\n\n\tEnter the seed pt. : ");
scanf("%d%d",&x,&y);


cleardevice();
setcolor(WHITE);

for(i=0;i<n;i++) /*- draw poly -*/
{
line(a[i][0],a[i][1],a[i+1][0],a[i+1][1]);
}

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

getch();
}

/*SAMPLE INPUT*/
/*Enter the number of edges of polygon 4

X0 Y0 = 50 50
X1 Y1 = 200 50
X2 Y2 = 200 300
X3 Y3 = 50 300

Enter the seed point 100 100*/