Huffman 树实现

#pragma once#include<iostream>using namespace std;template<typename T>class MinHeap{public:MinHeap(int n);~MinHeap();void BuildHeap();int Parent(int pos);int leftChild(int pos);int rightChild(int pos);bool isLeaf(int pos);bool Remove(int pos,T & node);bool Insert(const T & newNode);T & RemoveMin();void shiftDown(int pos);void shiftUp(int pos);void swap(int sizex,int sizey);//private:T * heapArray;int currentSize;int maxSize;};template<typename T>MinHeap<T>::MinHeap(int n){if(n <= 0){return;}maxSize = n;currentSize = 0;//数ºy组Á¨¦下?标À¨º从䨮0开a始º?heapArray = new T[maxSize];this->BuildHeap();}template<typename T>MinHeap<T>::~MinHeap(){delete heapArray;}template<typename T>void MinHeap<T>::BuildHeap(){for(int i = currentSize / 2 - 1; i >= 0 ; i--){ this->shiftDown(i);}}template<typename T>int MinHeap<T>::Parent(int pos){return (pos - 1) / 2;}template<typename T>int MinHeap<T>::leftChild(int pos){return (pos + 1) * 2 - 1;}template<typename T>int MinHeap<T>::rightChild(int pos){return (pos + 1) * 2;}template<typename T>bool MinHeap<T>::isLeaf(int pos){return (pos >= currentSize/2) && (pos < currentSize);}template<typename T>bool MinHeap<T>::Insert(const T & newNode){if(currentSize == maxSize){cerr<<"The heap is fulling."<<endl;return false;}heapArray[currentSize] = newNode;currentSize++;shiftUp(currentSize - 1);return true;}template<typename T>void MinHeap<T>::shiftDown(int pos){int i = pos; // 标À¨º识º?父?结¨¢点Ì?int j = leftChild (i); // 标À¨º识º?关?键¨¹值¦Ì较?小?的Ì?子Á¨®结¨¢点Ì?T temp = heapArray[i]; // 保À¡ê存ä?父?结¨¢点Ì?while (j < currentSize) { // 过y筛¦?if ((j < currentSize-1) && (heapArray[j]>heapArray[j + 1]))//若¨?有®D右®¨°子Á¨®节¨²点Ì?，ê?且¨°小?于®¨²左Á¨®子Á¨®节¨²点Ì?j++; // j指?向¨°右®¨°子Á¨®结¨¢点Ì?if (temp>heapArray[j]) { //若¨?父?节¨²点Ì?大䨮于®¨²子Á¨®节¨²点Ì?的Ì?值¦Ì则¨°交?换?位?置?heapArray[i] = heapArray[j];i = j;j = leftChild(j); }else break; //堆?序¨°满¨²足Á?，ê?跳¬?出?}heapArray[i] = temp;//ruguoniyuanyi}template<typename T>bool MinHeap<T>::Remove(int pos,T & node){if((pos < 0) || (pos >= currentSize)){cerr<<"The pos hvent node which name is "<<pos<<endl;return false;}node = heapArray[pos];heapArray[pos] = heapArray[--currentSize];if(heapArray[Parent(pos)] > heapArray[pos]){shiftUp(pos);}else{shiftDown(pos);}return true;}template<typename T>T & MinHeap<T>::RemoveMin(){if(currentSize <= 0){cerr<<"The heap is already empty."<<endl;exit(-1);}swap(0,--currentSize);// 交?换?堆?顶£¤和¨ª最Á?后¨®一°?个?元a素?if(currentSize > 1){shiftDown(0);}return heapArray[currentSize];}template<typename T>void MinHeap<T>::shiftUp(int pos){int temppos = pos;T temp = heapArray[temppos];while ((temppos>0) && (heapArray[Parent(temppos)]>temp)) { heapArray[temppos] = heapArray[Parent(temppos)];temppos = Parent(temppos);}heapArray[temppos] = temp;}template<typename T>void MinHeap<T>::swap(int sizex,int sizey){T temp = this->heapArray[sizex];this->heapArray[sizex] = this->heapArray[sizey];this->heapArray[sizey] = temp;}//HuffmanTreeNode.h#pragma oncetemplate<typename T>class HuffmanTreeNode{public:HuffmanTreeNode();bool operator < (HuffmanTreeNode<T> & obj2);bool operator > (HuffmanTreeNode<T> & obj2);//private:int element;T data;HuffmanTreeNode * rightchild;HuffmanTreeNode * leftchild;HuffmanTreeNode * parent;};template<typename T>bool HuffmanTreeNode<T>::operator < (HuffmanTreeNode<T> & obj2){ return this->element < obj2.element;}template<typename T>bool HuffmanTreeNode<T>::operator > (HuffmanTreeNode<T> & obj2){ return this->element > obj2.element;}template<typename T>HuffmanTreeNode<T>::HuffmanTreeNode(){element = 0;data = NULL;rightchild = NULL;leftchild = NULL;parent = NULL;}//HuffmanTree.h#pragma once#include"MinHeap.h"#include<queue>#include<fstream>#include<string>#include"HuffmanTreeNode.h"template<typename T>class HuffmanTree{public:HuffmanTree(int weight[],int n);~HuffmanTree(){};void MergeTree(HuffmanTreeNode<T> & ht1,HuffmanTreeNode<T> &ht2,HuffmanTreeNode<T> * parent);void DeleteTree(HuffmanTreeNode<T> * root);void levelOrder(HuffmanTreeNode<T> * root);void Generate();void Tranverse(HuffmanTreeNode<T> * pTree,string str);void preOrder(HuffmanTreeNode<T> * root){if(root != NULL){if(root->leftchild == NULL && root->rightchild == NULL)cout<<root->data<<endl;preOrder(root->leftchild);preOrder(root->rightchild);}}void decoding();HuffmanTreeNode<T> * root;};template<typename T>HuffmanTree<T>::HuffmanTree(int weight[],int n){//bulid the huffman treeMinHeap<HuffmanTreeNode<T>> heap(n);HuffmanTreeNode<T> * parent, * firstchild, * secondchild;HuffmanTreeNode<T> * NodeList = new HuffmanTreeNode<T>[n];int index = 0;for(int i = 0 ; i < n ; i++){if(weight[i] == 0){continue;}NodeList[index].element = weight[i];NodeList[index].data = i;NodeList[index].parent = NodeList[index].rightchild = NodeList[index].leftchild = NULL;heap.Insert(NodeList[index]);index++;}for(int i = 0 ; i < index - 1 ; i++){parent = new HuffmanTreeNode<T>;firstchild = new HuffmanTreeNode<T>();secondchild = new HuffmanTreeNode<T>();*firstchild = heap.RemoveMin();;*secondchild = heap.RemoveMin();MergeTree(*firstchild,*secondchild,parent);heap.Insert(*parent);root = parent;}delete [] NodeList;}template<typename T>//merge the ht1 tree and the ht2 tree...void HuffmanTree<T>::MergeTree(HuffmanTreeNode<T> &ht1,HuffmanTreeNode<T> & ht2,HuffmanTreeNode<T> * parent){ parent->leftchild = &ht1;parent->rightchild = &ht2;parent->element = ht1.element + ht2.element;parent->parent = NULL;ht1.parent = ht2.parent = parent;}template<typename T>void HuffmanTree<T>::levelOrder(HuffmanTreeNode<T> * root){ queue<HuffmanTreeNode<T> *> nodeQueue;//用队列储存将要访问的结点HuffmanTreeNode<T> * pointer = root;if(pointer != NULL){nodeQueue.push(pointer);}while(!nodeQueue.empty()){pointer = nodeQueue.front();//if(pointer->leftchild == NULL && pointer->rightchild == NULL)cout<<pointer->data<<endl;nodeQueue.pop();if(pointer->leftchild){nodeQueue.push(pointer->leftchild);}if(pointer->rightchild){nodeQueue.push(pointer->rightchild);}}}template<typename T>void HuffmanTree<T>::Generate(){//递归调用生成哈弗曼编码string str;this->Tranverse(root,str);}template<typename T>void HuffmanTree<T>::Tranverse(HuffmanTreeNode<T> * pointer,string str){if(pointer == NULL){return;}ofstream outFile;outFile.open("output.txt",ios_base::app);//采用追加操作if(!outFile){cerr<<"Can't open the output txt"<<endl;exit(-1);}if(pointer->leftchild == NULL && pointer->rightchild == NULL){//是叶结点，递归结束outFile<<pointer->data<<'\t'<<str<<endl;for(int i = 0 ; i < str.length() ; i++){code[pointer->data][i] = str[i];}//cout<<pointer->data<<" "<<str<<" "<<str.length()<<endl;outFile.close();return;}//非叶结点this->Tranverse(pointer->leftchild,str + "0");this->Tranverse(pointer->rightchild,str + "1");}template<typename T>void HuffmanTree<T>::decoding(){//解码，解读的decoding文件中01字符串，并将解读后的文件输出到屏幕ifstream inFile("decoding.txt");if(!inFile){cerr<<"Can't open the decoding.txt"<<endl;exit(-1);}char c = '0';HuffmanTreeNode<T> * pointer = root;while(inFile>>c){if(c == '1'){pointer = pointer->rightchild;}else if(c == '0'){pointer = pointer->leftchild;}else{return;}if(pointer->leftchild == NULL && pointer->rightchild == NULL){ cout<<pointer->data;pointer = root;}}}//main.cpp#include"HuffmanTree.h"#include<fstream>#include<iostream>using namespace std;int weight[128];//记录每个字符产生的次数char code[128][20];//记录每个字符对应产生的编码void reader_the_file(){//通过读文件得到weight[]memset(weight,0,sizeof(weight));ifstream inFile("input.txt");if(!inFile){cerr<<"Can't open the iutput.txt"<<endl;exit(-1);}char c = '0';while(inFile>>c){weight[(int)c]++;}inFile.close();}void fliter(){//fliter the number of the minimum nad maximum;int temp = 100000;int index = 0;for(int i = 0 ; i < 128 ; i++){//delete the maximum num if(weight[i] > 0){if(weight[i] < temp){temp = weight[i];index = i;}}}weight[index] = 0;temp = -1;for(int i = 0 ; i < 128 ; i++){//delete the minimum num if(weight[i] > 0){if(weight[i] > temp){temp = weight[i];index = i;}}}weight[index] = 0;}void encoding(){//编码，并将已经解码的后的结果存入decoding文件ifstream inFile("input.txt");if(!inFile){cerr<<"Can't open the iutput.txt"<<endl;exit(-1);}ofstream outFile;outFile.open("decoding.txt",ios_base::app);if(!outFile){cerr<<"Can't open the decodingt.txt"<<endl;exit(-1);}char c = '0';while(inFile>>c){outFile<<code[(int)c];}}int main(){reader_the_file();fliter();HuffmanTree<char> man(weight,128);man.Generate();//产生编码/* for(int i = 0 ; i < 128 ; i++){cout<<code[i]<<endl;}*/encoding();man.decoding();// man.levelOrder(man.root);// man.preOrder(man.root);return 0;}。