/* delete min value. multi-pass */
void heap_delete_min(heap *hp) {
heap_node *a,*b,*next_tmp,*new_root=NULL;
heap_node * h = hp->root;
/* until there is one node */
/* heap_node_meld in pairs, 1st and 2nd, 3rd and 4th, ...*/
while(h->first_child!=h->last_child) {
a = h->first_child;
while(a!=NULL)
{
next_tmp=NULL;
b = a->next_sibling;
heap_node_isolate(a);
if (b) {
next_tmp=b->next_sibling;
heap_node_isolate(b);
a = heap_node_meld(a,b);
}
h = heap_node_meld(h,a);
a = next_tmp;
}
}
if (h->first_child) {
new_root = h->first_child;
h->first_child->parent=NULL;
}
free(h);
hp->root = new_root;
}
/* decrease the value of the node */
void heap_decrease_key(heap *h, heap_node *node, int delta) {
node->value -= delta;
/* if the node is not at the root of the tree, remove it and
merge it with the root */
if (node!=h->root) {
/* remove the node tree from the siblings and parents*/
heap_node_isolate(node);
/* merge with root*/
h->root = heap_node_meld(h->root,node);
}
}
/* decrease the value of the node */
void heap_decrease_key(heap_node *node, foi new_weight) {
node->value.weight = new_weight;
/* if the node is not at the root of the tree, remove it and
merge it with the root */
if (node!=hp->root) {
/* remove the node tree from the siblings and parents*/
heap_node_isolate(node);
/* merge with root*/
hp->root = heap_node_meld(hp->root,node);
}
}
/* insert element to the heap */
heap_node * heap_insert(heap *h,int value) {
heap_node *node = heap_node_new(value);
h->root = heap_node_meld(h->root,node);
return node;
}
/* insert element to the heap */
heap_node * heap_insert(foi weight) {
heap_node *node = heap_node_new(weight);
hp->root = heap_node_meld(hp->root,node);
return node;
}
