优先级队列及小顶堆排序实现
/** @file HeapSort.h
* @copyright personal
* @brief 优先级队列及堆排序
* @version V1.0.0
* @author fangyuan
* @date 2015/12/31
* @note 测试版本
*/
#include "iostream"
using namespace std;
template<class T>
class CPriQueue
{
private:
int m_iIndex;
int m_iMaxsize;
T* m_pArray;
void swap(int i ,int j)
{
T t;
t = m_pArray[i];
m_pArray[i] = m_pArray[j];
m_pArray[j] = t;
}
void siftup()
{
int p;
for(int i = m_iIndex; i > 1 && m_pArray[p=i/2] > m_pArray[i]; i = p)
{
swap(p,i);
}
}
void siftdown()
{
int c;
for(int i = 1; (c=2*i) <= m_iIndex; i = c)//循环条件，有左结点
{
if(c+1 <= m_iIndex && m_pArray[c+1] < m_pArray[c])//右结点存在，且值比左结点小
{
c++;
}
if(m_pArray[i] <= m_pArray[c]) //当前结点值不大于左结点值，跳出循环
{
break;
}
swap(c,i);
}
}
public:
CPriQueue(int m)
{
m_iMaxsize = m;
m_pArray = new T[m_iMaxsize+1];
m_iIndex = 0;
}
void insert(T t)
{
if(m_iIndex >= m_iMaxsize)
{
cout << "堆大小超过最大值" << endl;
return;
}
m_pArray[++m_iIndex] = t;
siftup();//保持堆性质
}
T extract()
{
T value;
if(m_iIndex < 1)
{
cout << "此堆为空" << endl;
}
else
{
value = m_pArray[1];
m_pArray[1] = m_pArray[m_iIndex--];
siftdown();
}
return value;
}
//在原空间上进行排序，只使用一个单位额外空间
void heapSort()
{
int n = m_iIndex;//为了重用siftdown()
while(m_iIndex > 1)
{
swap(1,m_iIndex--);
siftdown();
}
m_iIndex = n;
}
void print()
{
for(int i = 1; i <= m_iIndex; ++i)
{
cout << m_pArray[i] << "\t";
}
cout << endl;
}
};
//优先级队列及堆排序测试
void priqueueTest()
{
CPriQueue<int> cp(100);
int value;
cout << "请输入需要插入堆的整数" << endl;
while(cin>>value)
{
cp.insert(value);
}
cp.print();
cout << cp.extract() << endl;
cp.print();
cp.heapSort();
cp.print();
}
int main()
{
//优先级队列
priqueueTest();
system("pause");
return 0;
}
//不足之处，欢迎指正。