| 15.4.4 Symmetric Case |
|
578. <Right-side rebalancing after PRB deletion 578> =
struct prb_node *w = f->prb_link[0];
if (w->prb_color == PRB_RED)
{
<Ensure w is black in right-side PRB deletion rebalancing 579>
}
if ((w->prb_link[0] == NULL
|| w->prb_link[0]->prb_color == PRB_BLACK)
&& (w->prb_link[1] == NULL
|| w->prb_link[1]->prb_color == PRB_BLACK))
{
<Case 1 in right-side PRB deletion rebalancing 580>
}
else
{
if (w->prb_link[0] == NULL
|| w->prb_link[0]->prb_color == PRB_BLACK)
{
<Transform right-side PRB deletion rebalancing case 3 into case 2 582>
}
<Case 2 in right-side PRB deletion rebalancing 581>
break;
}
This code is included in 571.
579. <Ensure w is black in right-side PRB deletion rebalancing 579> = w->prb_color = PRB_BLACK; f->prb_color = PRB_RED; f->prb_link[0] = w->prb_link[1]; w->prb_link[1] = f; g->prb_link[g->prb_link[0] != f] = w; w->prb_parent = f->prb_parent; f->prb_parent = w; g = w; w = f->prb_link[0]; w->prb_parent = f;
This code is included in 578.
580. <Case 1 in right-side PRB deletion rebalancing 580> = w->prb_color = PRB_RED;
This code is included in 578.
581. <Case 2 in right-side PRB deletion rebalancing 581> = w->prb_color = f->prb_color; f->prb_color = PRB_BLACK; w->prb_link[0]->prb_color = PRB_BLACK; f->prb_link[0] = w->prb_link[1]; w->prb_link[1] = f; g->prb_link[g->prb_link[0] != f] = w; w->prb_parent = f->prb_parent; f->prb_parent = w; if (f->prb_link[0] != NULL) f->prb_link[0]->prb_parent = f;
This code is included in 578.
582. <Transform right-side PRB deletion rebalancing case 3 into case 2 582> = struct prb_node *y = w->prb_link[1]; y->prb_color = PRB_BLACK; w->prb_color = PRB_RED; w->prb_link[1] = y->prb_link[0]; y->prb_link[0] = w; if (w->prb_link[1] != NULL) w->prb_link[1]->prb_parent = w; w = f->prb_link[0] = y; w->prb_link[0]->prb_parent = w;
This code is included in 578.