最小堆模板类 面试必备

面试必会

#include <iostream>using namespace std;template<class T>class MinHeap{private:T *heap; //元素数组，0号位置也储存元素int CurrentSize; //目前元素个数int MaxSize; //可容纳的最多元素个数void FilterDown(const int start,const int end); //自上往下调整，使关键字小的节点在上void FilterUp(int start); //自下往上调整public:MinHeap(int n=1000);~MinHeap();bool Insert(const T &x); //插入元素T RemoveMin(); //删除最小元素T GetMin(); //取最小元素bool IsEmpty() const;bool IsFull() const;void Clear();};template<class T>MinHeap<T>::MinHeap(int n){MaxSize=n;heap=new T[MaxSize];CurrentSize=0;}template<class T>MinHeap<T>::~MinHeap(){delete []heap;}template<class T>void MinHeap<T>::FilterUp(int start) //自下往上调整{int j=start,i=(j-1)/2; //i指向j的双亲节点T temp=heap[j];while(j>0){if(heap[i]<=temp)break;else{heap[j]=heap[i];j=i;i=(i-1)/2;}}heap[j]=temp;}template<class T>void MinHeap<T>::FilterDown(const int start,const int end) //自上往下调整，使关键字小的节点在上{int i=start,j=2*i+1;T temp=heap[i];while(j<=end){if( (j<end) && (heap[j]>heap[j+1]) )j++;if(temp<=heap[j])break;else{heap[i]=heap[j];i=j;j=2*j+1;}}heap[i]=temp;}template<class T>bool MinHeap<T>::Insert(const T &x){if(CurrentSize==MaxSize)return false;heap[CurrentSize]=x;FilterUp(CurrentSize);CurrentSize++;return true;}template<class T>T MinHeap<T>::RemoveMin( ){T x=heap[0];heap[0]=heap[CurrentSize-1];CurrentSize--;FilterDown(0,CurrentSize-1); //调整新的根节点return x;}template<class T>T MinHeap<T>::GetMin(){return heap[0];}template<class T>bool MinHeap<T>::IsEmpty() const{return CurrentSize==0;}template<class T>bool MinHeap<T>::IsFull() const{return CurrentSize==MaxSize;}template<class T>void MinHeap<T>::Clear(){CurrentSize=0;}//最小堆：根结点的键值是所有堆结点键值中最小者。int main (){int k,n=11,a[11]={0,5,2,4,9,7,3,1,10,8,6};MinHeap<int> test(11);for(k=0; k<n; k++)test.Insert(a[k]);cout<<test.IsFull()<<endl;for(k=0;k<n;k++)cout<<test.RemoveMin()<<ends;cout<<endl;return 0;}

参考：http://baike.baidu.com/link?url=euAoHK32V65qT08sjVg4iqD1Spi4YAV6DSTnnGto0IGCVTGRglzRwH1qHrjS4x1exyKWgClVwTqLnP2LCdt4ba