You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
93 lines
2.5 KiB
93 lines
2.5 KiB
//
|
|
// HtHeap.h
|
|
//
|
|
// HtHeap: A Heap class which holds objects of type Object.
|
|
// (A heap is a semi-ordered tree-like structure.
|
|
// it ensures that the first item is *always* the largest.
|
|
// NOTE: To use a heap, you must implement the Compare() function for
|
|
// your Object classes. The assumption used here is -1 means
|
|
// less-than, 0 means equal, and +1 means greater-than. Thus
|
|
// this is a "min heap" for that definition.)
|
|
//
|
|
// Part of the ht://Dig package <http://www.htdig.org/>
|
|
// Copyright (c) 1999-2004 The ht://Dig Group
|
|
// For copyright details, see the file COPYING in your distribution
|
|
// or the GNU Library General Public License (LGPL) version 2 or later
|
|
// <http://www.gnu.org/copyleft/lgpl.html>
|
|
//
|
|
// $Id: HtHeap.h,v 1.7 2004/05/28 13:15:20 lha Exp $
|
|
//
|
|
//
|
|
#ifndef _HtHeap_h_
|
|
#define _HtHeap_h_
|
|
#include "Object.h"
|
|
#include "HtVector.h"
|
|
|
|
class HtHeap : public Object
|
|
{
|
|
public:
|
|
//
|
|
// Constructor/Destructor
|
|
//
|
|
HtHeap();
|
|
HtHeap(HtVector vector);
|
|
~HtHeap();
|
|
|
|
//
|
|
// Add() will add an Object to the heap in the appropriate location
|
|
//
|
|
void Add(Object *);
|
|
|
|
//
|
|
// Destroy() will delete all the objects in the heap. This is
|
|
// equivalent to calling the destructor
|
|
//
|
|
void Destroy();
|
|
|
|
//
|
|
// Peek() will return a reference to the top object in the heap.
|
|
//
|
|
Object *Peek() {return data->Nth(0);}
|
|
|
|
//
|
|
// Remove() will return a reference as Peek() but will also
|
|
// remove the reference from the heap and re-heapify
|
|
//
|
|
Object *Remove();
|
|
|
|
//
|
|
// Access to the number of elements
|
|
//
|
|
int Count() {return data->Count();}
|
|
int IsEmpty() {return data->IsEmpty();}
|
|
|
|
//
|
|
// Deep copy member function
|
|
//
|
|
Object *Copy() const;
|
|
|
|
//
|
|
// Assignment
|
|
//
|
|
HtHeap &operator= (HtHeap *heap) {return *this = *heap;}
|
|
HtHeap &operator= (HtHeap &heap);
|
|
|
|
protected:
|
|
// The vector class should keep track of everything for us
|
|
HtVector *data;
|
|
|
|
// Functions for establishing the relations between elements
|
|
int parentOf (int i)
|
|
{ return (i - 1)/2; }
|
|
int leftChildOf (int i)
|
|
{ return 2*i + 1; }
|
|
int rightChildOf (int i)
|
|
{ return 2* (i+1); }
|
|
|
|
// Protected procedures for performing heap-making operations
|
|
void percolateUp (int leaf); // pushes the node up as far as possible
|
|
void pushDownRoot (int root); // pushes the node down as necessary
|
|
};
|
|
|
|
#endif
|