Heap，堆，大堆和小堆用仿函数实现

#pragma once
#include<iostream>
#include<vector>
using namespace std;
template<class T>
class Heap
{
public:
//vector调用自己的构造函数
Heap()
{}
Heap(T* a, size_t size)
{
for (size_t i = 0; i < size; ++i)
_array.push_back(a[i]);
//size-1是数组最大下标，再减1除二是父节点下标
for (int i = (_array.size() - 1 - 1) / 2; i >= 0; --i)
{
AdjustDown(i);
}
}
void Push(const T& x)
{
_array.push_back(x);
AdjustUp(_array.size()-1);
}
void Pop()
{
if (_array.size()>0)
{
swap(_array[_array.size() - 1],_array[0]);
_array.pop_back();
AdjustDown(0);
}
}
protected:
void AdjustDown(int prtIndex)
{
int leftIndex = 0;
while (prtIndex<_array.size())
{
leftIndex = prtIndex * 2 + 1;
if (leftIndex + 1 < _array.size() && _array[leftIndex + 1] < _array[leftIndex])
leftIndex = leftIndex + 1;
if (leftIndex<_array.size() && _array[prtIndex] > _array[leftIndex])
{
swap(_array[prtIndex], _array[leftIndex]);
prtIndex = leftIndex;
}
else
break;
}
}
void AdjustUp(int  chiIndex)
{
int parIndex = (chiIndex - 1) / 2;
while (chiIndex > 0)//父节点不会小于0，（0-1）/2等于0，此处应用chiIndex来判断
{
if (_array[parIndex] > _array[chiIndex])
{
swap(_array[parIndex], _array[chiIndex]);
chiIndex = parIndex;
parIndex = (chiIndex - 1) / 2;
}
else
break;
}
}
protected:
vector<T> _array;
};

#include"Heap.h"
void Test1()
{
int array[10] = { 10, 2, 3, 4, 8, 1, 6, 5, 9, 7 };
Heap<int> h1(array,10);
h1.Push(0);
h1.Pop();

}

#pragma once
#include<iostream>
#include<vector>
using namespace std;
//仿函数：指一个类满足函数operator,此时是比较大小
template<class T>
struct Great
{
bool operator()(const T& l, const T& r)
{
return l > r;
}
};
template<class T>
struct Less
{
bool operator()(const T& l, const T& r)
{
return l < r;
}
};
template<class T,class Comp=Less<int>>
class Heap
{
public:
//vector调用自己的构造函数
Heap()
{}
Heap(T* a, size_t size)
{
for (size_t i = 0; i < size; ++i)
_array.push_back(a[i]);
//size-1是数组最大下标，再减1除二是父节点下标
for (int i = (_array.size() - 1 - 1) / 2; i >= 0; --i)
{
AdjustDown(i);
}
}
void Push(const T& x)
{
_array.push_back(x);
AdjustUp(_array.size() - 1);
}
void Pop()
{
if (_array.size()>0)
{
swap(_array[_array.size() - 1], _array[0]);
_array.pop_back();
AdjustDown(0);
}
}
protected:
void AdjustDown(int prtIndex)
{
int leftIndex = 0;
while (prtIndex<_array.size())
{
leftIndex = prtIndex * 2 + 1;
//此处应对称方法，传递的参数，比较大小：
if (leftIndex + 1 < _array.size() && _com(_array[leftIndex + 1] , _array[leftIndex]))
leftIndex = leftIndex + 1;
if (leftIndex<_array.size() && _com(_array[leftIndex],_array[prtIndex]))
{
swap(_array[prtIndex], _array[leftIndex]);
prtIndex = leftIndex;
}
else
break;
}
}
void AdjustUp(int  chiIndex)
{
int parIndex = (chiIndex - 1) / 2;
while (chiIndex > 0)//父节点不会小于0，（0-1）/2等于0，此处应用chiIndex来判断
{
if (_com(_array[chiIndex], _array[parIndex]))
{
swap(_array[parIndex], _array[chiIndex]);
chiIndex = parIndex;
parIndex = (chiIndex - 1) / 2;
}
else
break;
}
}
protected:
vector<T> _array;
Comp _com;
};

void Test2()
{
int array[10] = { 10, 2, 3, 4, 8, 1, 6, 5, 9, 7 };
Heap<int,Great<int>> h1(array,10);
h1.Push(100);
h1.Pop();
}