堆排序的练习

//HeapSorter.h

#pragma once

#include <stdlib.h>

#include <stdio.h>

class HeapSorter

{

public:

HeapSorter(int nVecLength);

~HeapSorter(void);

protected:

HeapSorter()

{

m_pVect = NULL;

m_nVecLens = 0;

}

public:

void RandomValueVector();

void OutputVector();

void MinHeapSortToDescendArray(); //最小堆的降序排序

protected:

void MinHeapFixup(int *pArr, int i); //数组i元素更新到小堆的插入操作

//调整i节点的位置更新至正确的小堆：小堆的i节点下沉

void MinHeapFixdown(int *pArr, int i, int n);

void MakeMinHeap(int *pArr, int n); //从乱序数组建立最小堆

protected:

int *m_pVect;

int m_nVecLens;

};

//HeapSorter.cpp

#include "HeapSorter.h"

#include <time.h>

#include <assert.h>

HeapSorter::HeapSorter(int nVecLength)

{

m_nVecLens = nVecLength;

if(m_nVecLens > 0)

{

m_pVect = new int[m_nVecLens];

}

else

m_pVect = NULL;

srand(time(NULL));

}

HeapSorter::~HeapSorter(void)

{

if(m_pVect)

{

delete []m_pVect;

m_pVect = NULL;

}

}

void HeapSorter::RandomValueVector()

{

int *ptr=m_pVect;

for(int i=0; i < m_nVecLens; i++)

{

*ptr++ = rand();

}

}

void HeapSorter::MinHeapFixup(int *pArr, int i)

{

assert(pArr && i > 0);

int j, temp;

temp = pArr[i];

j = (i -1) / 2; //父节点

while(j >= 0 && i > 0)

{

if(pArr[j] <= temp)

break;

pArr[i] = pArr[j];

i = j;

j = (i -1) / 2; //父节点

}

pArr[i] = temp;

}

void HeapSorter::MinHeapFixdown(int *pArr, int i, int n)

{

assert(pArr && i >= 0 && n > 0);

int j, temp;

temp = pArr[i];

j = 2*i + 1; //第一个子节点

while(j < n)

{

if(j + 1 < n && pArr[j+1] < pArr[j])

j++;

if(pArr[j] >= temp)

break;

pArr[i] = pArr[j];

i = j;

j = 2*i + 1; //第一个子节点

}

pArr[i] = temp;

}

void HeapSorter::MakeMinHeap(int *pArr, int n)

{

assert(pArr && n > 0);

for(int i = n / 2 - 1; i >= 0; i--)

{

MinHeapFixdown(pArr, i, n);

}

}

void HeapSorter::MinHeapSortToDescendArray()

{

assert(m_pVect && m_nVecLens > 0);

MakeMinHeap(m_pVect, m_nVecLens);

int temp = 0;

for(int i = m_nVecLens - 1; i > 0; i--)

{

temp = m_pVect[i];

m_pVect[i] = m_pVect[0];

m_pVect[0] = temp;

MinHeapFixdown(m_pVect, 0, i);

}

}

void HeapSorter::OutputVector()

{

int lineNum = 20;

for(int i = 0; i < m_nVecLens; i++)

{

printf("%5d", m_pVect[i]);

if(i % lineNum == lineNum - 1)

{

printf("\n");

}

else

printf("\t");

}

printf("\n\n");

}

//main.cpp

#include <stdlib.h>

#include <stdio.h>

#include "HeapSorter.h"

int main()

{

HeapSorter sorter(100);

sorter.RandomValueVector();

sorter.OutputVector();

sorter.MinHeapSortToDescendArray();

sorter.OutputVector();

sorter.RandomValueVector();

sorter.OutputVector();

sorter.MinHeapSortToDescendArray();

sorter.OutputVector();

printf("press any key to exit:");

getchar();

}