//
// Enforce heap property on a path in the tree
//
static void heapify(PQueue* pq, unsigned int root) {
unsigned int min_index = root;
unsigned int lc = heap_lchild(root);
unsigned int rc = heap_rchild(root);
assert(pq && pq->elements);
if ((lc < pq->cursize) &&
(getPriority(pq->elements[lc]) < getPriority(pq->elements[min_index]))) {
min_index = lc;
}
if ((rc < pq->cursize) &&
(getPriority(pq->elements[rc]) < getPriority(pq->elements[min_index]))) {
min_index = rc;
}
if (min_index != root) {
PQ_elemType tmp_q = pq->elements[min_index];
pq->elements[min_index] = pq->elements[root];
pq->elements[root] = tmp_q;
// This is triangle specific: Need to update triangle's pointer to
// itself in the PQ
pq->elements[min_index]->pqIndex = min_index;
pq->elements[root]->pqIndex = root;
heapify(pq, min_index);
}
}
static void heapify(PQueue* pq, unsigned int root) {
unsigned int min_index = root;
unsigned int lc = heap_lchild(root);
unsigned int rc = heap_rchild(root);
assert(pq && pq->elements);
if ((lc < pq->cursize) &&
(compare_element(pq->elements[lc], pq->elements[min_index]) < 0)) {
min_index = lc;
}
if ((rc < pq->cursize) &&
(compare_element(pq->elements[rc], pq->elements[min_index]) < 0)) {
min_index = rc;
}
if (min_index != root) {
elemType tmp_q = pq->elements[min_index];
pq->elements[min_index] = pq->elements[root];
pq->elements[root] = tmp_q;
heapify(pq, min_index);
}
}
