C++实现哈夫曼树编码解码
本文实例为大家分享了C++实现哈夫曼树的编码解码，供大家参考，具体内容如下
代码：
#pragma once
#include<iostream>
#include<stack>
using namespace std;
#define m 20
stack<int> s;
/*哈夫曼树结点类HuffmanNode声明*/
template<class T>
class HuffmanNode {
private:
HuffmanNode<T> * left;
HuffmanNode<T> * right;
T data;
int weight;
public:
HuffmanNode(){}
HuffmanNode(const T& item, HuffmanNode<T> * l, HuffmanNode<T> * r):data(item),left(l),right(r){}
HuffmanNode<T> * getLeft() { return left; }
void setLeft(HuffmanNode<T> * left) { this->left = left; }
HuffmanNode<T> * getRight() { return right; }
void setRight(HuffmanNode<T> * right) { this->right=right; }
T& getData() { return data; }
void setData(const T& item) { data = item; }
int getWeight() { return weight; }
void setWeight(int weight) { this->weight = weight; }
};
/*哈夫曼树类HuffmanTree声明*/
template<class T>
class HuffmanTree {
private:
HuffmanNode<T> * root;
T data[m];
int weight[m];
int count;
public:
HuffmanTree(HuffmanNode<T> * t=NULL):root(t){}
void CreateHuffmanTree();//创建哈夫曼树
HuffmanNode<T> * getRoot() { return root; }
void setRoot(HuffmanNode<T> * t) { root = t; }
void inputNodes();//输入各个结点的data和weight值
HuffmanNode<T> * deCode(HuffmanNode<T>*t,T item);
void showCode();
};
template<class T>
inline void HuffmanTree<T>::CreateHuffmanTree()
{
inputNodes();
HuffmanNode<T> ** H = new HuffmanNode<T>*[count];
HuffmanNode<T> * p1 = NULL, *p2 = NULL, * p,* t;
for (int i = 0; i < count; i++) {
H[i] = new HuffmanNode<T>();
H[i]->setData(data[i]);
H[i]->setWeight(weight[i]);
H[i]->setLeft(NULL);
H[i]->setRight(NULL);
}
for (int i = 0; i < count - 1; i++) {
p = new HuffmanNode<T>();
p1 = H[i];
p2 = H[i + 1];
p->setLeft(p1);
p->setRight(p2);
p->setWeight(p1->getWeight() + p2->getWeight());
//将新的结点插入结点数组中的合适位置,并将被合并的两个结点删除
t = p;
int j = i + 2;
while ( j < count &&H[j]->getWeight() < t->getWeight()) {
H[j - 1] = H[j];
j++;
}
H[j - 1] = t;
}
root = H[count - 1];
}
template<class T>
inline void HuffmanTree<T>::inputNodes()
{
int i = 0;
for (int j = 0; j < m; j++) {
data[j] = NULL;
weight[j] = 0;
}
while (cin >> data[i] >> weight[i]) {
i++;
}
count = i;
}
template<class T>
inline HuffmanNode<T>* HuffmanTree<T>::deCode( HuffmanNode<T> * t,T item)
{
HuffmanNode<T> * p, * q;
if(t==NULL)
return NULL;
if (t->getData() == item)
return t;
if ((p = deCode(t->getLeft(), item))!=NULL) {
s.push(0);
return p;
}
else if((q = deCode(t->getRight(), item))!=NULL){
s.push(1);
return q ;
}
}
template<class T>
inline void HuffmanTree<T>::showCode()
{
cout << root->getWeight() << endl;
cout << (root->getLeft())->getRight()->getData() << endl;
for (int i = 0; i < count; i++) {
cout << data[i] << "——";
deCode(root, data[i]);
while (!s.empty()) {
cout << s.top();
s.pop();
}
cout << endl;
}
}
测试程序：
#include<iostream>
#include"HuffmanTree.h"
using namespace std;
int main() {
HuffmanTree<char> * tree = new HuffmanTree<char>();
tree->CreateHuffmanTree();
tree->showCode();
system("pause");
return 0;
}
测试数据：
n 1
s 3
t 4
a 10
i 12
p 13
e 15
Ctrl+Z 回车结束输入
输入时权值由小到大排序…也可以在程序里加一个排序
结果：
