rapid7/metasploit-framework

#ifndef __HEAP_H__
#define __HEAP_H__

#include "vector.h"


/* Make heap from range
 * Rearranges the elements in the range [first,last) in such a way that they form a heap.
 * A heap is a way to organize the elements of a range that allows for fast retrieval of the element with the highest
 * value at any moment (with pop_heap), even repeatedly, while allowing for fast insertion of new elements (with
 * push_heap).
 * The element with the highest value is always pointed by first. The order of the other elements depends on the
 * particular implementation, but it is consistent throughout all heap-related functions of this header.
 * The elements are compared using cmp.
 */
void Make_Heap(Vector *v, size_t first, size_t last, int (*cmp)(void *, void *));


/* Push element into heap range
 * Given a heap in the range [first,last-1), this function extends the range considered a heap to [first,last) by
 * placing the value in (last-1) into its corresponding location within it.
 * A range can be organized into a heap by calling make_heap. After that, its heap properties are preserved if elements
 * are added and removed from it using push_heap and pop_heap, respectively.
 */
void Heap_Push(Vector *v, size_t first, size_t last, int (*cmp)(void *, void *));


/* Pop element from heap range
 * Rearranges the elements in the heap range [first,last) in such a way that the part considered a heap is shortened
 * by one: The element with the highest value is moved to (last-1).
 * While the element with the highest value is moved from first to (last-1) (which now is out of the heap), the other
 * elements are reorganized in such a way that the range [first,last-1) preserves the properties of a heap.
 * A range can be organized into a heap by calling make_heap. After that, its heap properties are preserved if elements
 * are added and removed from it using push_heap and pop_heap, respectively.
 */
void Heap_Pop(Vector *v, size_t first, size_t last, int (*cmp)(void *, void *));

#endif //__HEAP_H__