int solve()
{
int i, j;
for (i = 0; i < n*2; i+=2)
{
if (v[i].tf == 0 && v[i^1].tf == 0)
{
ST_RESET();
if(dfs(i) == 0)
{
/* restore previos dfs */
while (!ST_IS_EMPTY()) {
ST_POP(j);
v[j].tf = 0;
}
/* try another path */
if(dfs(i^1) == 0)
return 0;
}
}
}
return 1;
}
static struct i_bitmap *
i_flood_fill_low(i_img *im,i_img_dim seedx,i_img_dim seedy,
i_img_dim *bxminp, i_img_dim *bxmaxp, i_img_dim *byminp, i_img_dim *bymaxp,
i_color const *seed, ff_cmpfunc cmpfunc) {
i_img_dim ltx, rtx;
i_img_dim tx = 0;
i_img_dim bxmin = seedx;
i_img_dim bxmax = seedx;
i_img_dim bymin = seedy;
i_img_dim bymax = seedy;
struct llist *st;
struct i_bitmap *btm;
int channels;
i_img_dim xsize,ysize;
i_color cval;
channels = im->channels;
xsize = im->xsize;
ysize = im->ysize;
btm = btm_new(xsize, ysize);
st = llist_new(100, sizeof(struct stack_element*));
/* Find the starting span and fill it */
ltx = i_lspan(im, seedx, seedy, seed, cmpfunc);
rtx = i_rspan(im, seedx, seedy, seed, cmpfunc);
for(tx=ltx; tx<=rtx; tx++) SET(tx, seedy);
bxmin = ltx;
bxmax = rtx;
ST_PUSH(ltx, rtx, ltx, rtx, seedy+1, 1);
ST_PUSH(ltx, rtx, ltx, rtx, seedy-1, -1);
while(st->count) {
/* Stack variables */
i_img_dim lx,rx;
i_img_dim dadLx,dadRx;
i_img_dim y;
int direction;
i_img_dim x;
int wasIn=0;
ST_POP(); /* sets lx, rx, dadLx, dadRx, y, direction */
if (y<0 || y>ysize-1) continue;
if (bymin > y) bymin=y; /* in the worst case an extra line */
if (bymax < y) bymax=y;
x = lx+1;
if ( lx >= 0 && (wasIn = INSIDE(lx, y, seed)) ) {
SET(lx, y);
lx--;
while(lx >= 0 && INSIDE(lx, y, seed)) {
SET(lx,y);
lx--;
}
}
if (bxmin > lx) bxmin = lx;
while(x <= xsize-1) {
/* printf("x=%d\n",x); */
if (wasIn) {
if (INSIDE(x, y, seed)) {
/* case 1: was inside, am still inside */
SET(x,y);
} else {
/* case 2: was inside, am no longer inside: just found the
right edge of a span */
ST_STACK(direction, dadLx, dadRx, lx, (x-1), y);
if (bxmax < x) bxmax = x;
wasIn=0;
}
} else {
if (x > rx) goto EXT;
if (INSIDE(x, y, seed)) {
SET(x, y);
/* case 3: Wasn't inside, am now: just found the start of a new run */
wasIn = 1;
lx = x;
} else {
/* case 4: Wasn't inside, still isn't */
}
}
x++;
}
EXT: /* out of loop */
if (wasIn) {
/* hit an edge of the frame buffer while inside a run */
ST_STACK(direction, dadLx, dadRx, lx, (x-1), y);
if (bxmax < x) bxmax = x;
}
}
llist_destroy(st);
*bxminp = bxmin;
*bxmaxp = bxmax;
*byminp = bymin;
*bymaxp = bymax;
return btm;
}
