#include <iostream>
using namespace std;
#include <vector>
#include <assert.h>
//仿函数
template<class T>
struct Less
{
bool operator()(const T& left, const T& right)
{
return left < right;
}
};
template<class T>
struct Greater
{
bool operator()(const T& left, const T& right)
{
return left > right;
}
};
template<class T, class Compare = Less<T>>//默认为小堆
class Heap
{
public:
Heap()
{}
Heap(const T* array, size_t size)
{
for (size_t i = 0; i < size; ++i)
{
_a.push_back(array[i]);
}
for (size_t i = (_a.size()-2)/2; i < _a.size(); --i)
{
_AdjustDown(i);
}
}
void Push(const T& x)
{
_a.push_back(x);
_AdjustUp(_a.size()-1);
}
void Pop()
{
assert(!_a.empty());
swap(_a[0], _a[_a.size()-1]);
_a.pop_back();
_AdjustDown(0);
}
T& GetTop()
{
assert(!_a.empty());
return _a[0];
}
bool Empty()
{
return _a.empty();
}
size_t Size()
{
return _a.size();
}
void Print()
{
for (size_t i = 0; i < _a.size(); ++i)
{
cout<<_a[i]<<" ";
}
cout<<endl;
}
protected:
//向下调整
void _AdjustDown(size_t parent)
{
Compare compare;
size_t child = parent*2 + 1;
while (child < _a.size())
{
//比较左右孩子
if (child+1 < _a.size()
&& compare(_a[child+1], _a[child]))
{
++child;
}
if (compare(_a[child], _a[parent]))
{
swap(_a[child], _a[parent]);
parent = child;
child = parent*2 + 1;
}
else
{
break;
}
}
}
//向上调整
void _AdjustUp(size_t child)
{
Compare compare;
size_t parent = (child-1)/2;
while (child > 0)
{
if (compare(_a[child], _a[parent]))
{
swap(_a[parent], _a[child]);
child = parent;
parent = (child-1)/2;
}
else
{
break;
}
}
}
protected:
vector<T> _a;
};
void Test()
{
int a[10] = {10, 11, 13, 12, 16, 18, 15, 17, 14, 19};
Heap<int, Greater<int>> hp1(a, sizeof(a)/sizeof(a[0]));
hp1.Print();
cout<<"size:"<<hp1.Size()<<endl;
cout<<"top:"<<hp1.GetTop()<<endl;
cout<<"empty:"<<hp1.Empty()<<endl;
}
int main()
{
Test();
return 0;
}
本文出自 “zgw285763054” 博客，请务必保留此出处http://zgw285763054.blog.51cto.com/11591804/1785308
原文地址：http://zgw285763054.blog.51cto.com/11591804/1785308
