internal void pqdownheap(short[] tree, int k)
{
int v = heap[k];
int j = k << 1; // left son of k
while (j <= heap_len)
{
// Set j to the smallest of the two sons:
if (j < heap_len && smaller(tree, heap[j + 1], heap[j], depth))
{
j++;
}
// Exit if v is smaller than both sons
if (smaller(tree, v, heap[j], depth))
break;
// Exchange v with the smallest son
heap[k] = heap[j]; k = j;
// And continue down the tree, setting j to the left son of k
j <<= 1;
}
heap[k] = v;
}