c++ 数据结构 哈夫曼树

      给定n个权值作为n的叶子结点，构造一棵二叉树，若带权路径长度达到最小，称这样的二叉树为最优二叉树，也称为哈夫曼树(Huffman Tree)。哈夫曼树是带权路径长度最短的树，权值较大的结点离根较近。

     代码如下：（代码为老师所给）

#include<iostream>using namespace std;struct HTNode //哈夫曼树节点；{char ch;int weight,parent,lchild,rchild;};class HuffmanTree //哈夫曼树树{public:HuffmanTree(int n,char a[],int w[]){m_Htsize=0;m_Ht=NULL;_Create(n,a,w);}~HuffmanTree(){delete [] m_Ht;}void print();//打印哈夫曼树；private:int m_Htsize;HTNode* m_Ht;void _Create(int n,char a[],int w[]);//构建哈夫曼树树int _MinVal(const int & i);void _Select(int i,int &s1,int &s2);};void HuffmanTree::_Create(int n,char a[],int w[]){int s1=-1,s2=-1,i;m_Ht=new HTNode[2*n-1];m_Htsize=2*n-1;for(i=0;i<n;i++){m_Ht[i].ch=a[i];m_Ht[i].weight=w[i];m_Ht[i].lchild=-1;m_Ht[i].rchild=-1;m_Ht[i].parent=-1;}for(;i<2*n-1;i++){_Select(i,s1,s2);m_Ht[s1].parent=i;m_Ht[s2].parent=i;m_Ht[i].weight=m_Ht[s1].weight+m_Ht[s2].weight;m_Ht[i].lchild=s1;m_Ht[i].rchild=s2;m_Ht[i].parent=-1;}}//找到第i个节点前权重最小的节点int HuffmanTree::_MinVal(const int & i){int x=10000,k=0;for(int j=0;j<i;j++){if(m_Ht[j].parent==-1&&m_Ht[j].weight<x)if(m_Ht[j].weight<x){x=m_Ht[j].weight;k=j;}}m_Ht[k].parent=10000;return k;}//找到第i个节点前权重最小的两个void HuffmanTree::_Select(int i,int &s1,int &s2){s1=_MinVal(i);s2=_MinVal(i);}void HuffmanTree::print(){   int i;    cout << "所建哈夫曼树的静态链表表示如下：" << endl;    cout << "位置    " << "字符    " << "权值    "          << "双亲    " << "左孩子  " << "右孩子" << endl;     for(i = 0;i<(m_Htsize+1)/2; i++){        cout << " " << i << "       " << m_Ht[i].ch                          << "        " << m_Ht[i].weight << "      ";        cout << m_Ht[i].parent << "       "              << m_Ht[i].lchild << "       " << m_Ht[i].rchild << endl;    }    for (; i < m_Htsize; i++){        cout << " " << i << "               " << m_Ht[i].weight                          << "      " << m_Ht[i].parent << "        ";        cout << m_Ht[i].lchild << "       " << m_Ht[i].rchild << endl;     }    cout << endl;     }int main(){int n;    cout << "请输入树叶结点的个数(小于等于1结束)：" << endl;    cin>>n;    char chA[256];    int weightA[256];    for(int i= 0 ; i < n; i++){        cout << "请输入第" << i << "个字符及权值" << endl;        cin >> chA[i] >> weightA[i];    }    HuffmanTree ht(n,chA,weightA);ht.print();return 0;}