Paint Fill

/***

9.7

Implement the "paint fill" function that one might see on many image editing programs. That is, given a screen (represented by a two-dimensional array of colors), a point, and a new color, fill in the surrounding area until the color changes from the original color.

***/

#include<iostream>

using namespace std;

void paintfill(int *a, int color, int org, int x, int y, int sz) {

       if(x < 0 || y < 0 || x > sz-1 || y > sz-1) return;

       if(*(a+x*sz+y) != org || *(a+x*sz+y) == color) return;

       *(a+x*sz+y) = color;

       paintfill(a, color, org, x-1, y, sz);

       paintfill(a, color, org, x+1, y, sz);

       paintfill(a, color, org, x, y-1, sz);

       paintfill(a, color, org, x, y+1, sz);

}

void main() {

       int a[] = {0, 0, 0, 0, 0, 0, 1, 0, 0};

       paintfill(a, 2, 0, 1, 1, 3);

       for (int i = 0; i<3; i++)

       {

              for (int j=0; j<3; j++)

              {

                     cout<<a[i*3+j]<<" ";

              }

              cout<<endl;

       }

}