#include <iostream>
using namespace std;
#define LEAFNUM 10        //叶子节点数，也就是权值树
#define HUFNUM 2*LEAFNUM
#define MAXWEIGHT 999.9
//*********存储结构***********
class HufTree;
//***** Node**********
class NODE
{
private:
 char Data;          //节点的数据域
 double Weight;   //节点的权值域
 int Lchild,Rchild,Parent;   //节点的左孩子右孩子及双亲域
public:
 NODE()            //构造函数
 {
 Data = '\0';
 Weight = 0;
 Lchild = -1;
 Rchild = -1;
 Parent = -1;        //给节点的数据初始化
 }
 int Re_L(){return Lchild;}
 int Re_R(){return Rchild;}
 char Re_Data(){return Data;}
 double Re_Weight(){return Weight;}
 friend class HufTree;     //声明友元
};//Node

//********HufTree类**********
class HufTree
{
private:
 int NodeNum;
 NODE HufArry[HUFNUM];
public:
 HufTree(){NodeNum = 0;}
 void SetHuf(int,double,char);   //设置权值与数据域
 void CreatHuf();          //创建哈夫曼树
 void SelectMin(int,int&,int&);   //查找哈夫曼树种两个权值最小的树
 void Find_Root_and_Print();       //查找树根节点位置
 void PrintHuf(int);          //遍历哈夫曼树
};//huftree
 
void HufTree::SetHuf(int i,double wei,char ch)
{
 HufArry[i].Data = ch;
 HufArry[i].Weight = wei;
}
void HufTree::CreatHuf()
{
 cout<<"每次查询两个最小树的位置:"<<endl;
 for(int i = LEAFNUM; i < HUFNUM - 1; i++)
 {
 int p1 = 0;
 int p2 = 0;
 SelectMin(i,p1,p2);           //找出当前树种权值最小的两颗树 
 cout<<p1<<"   < - >    "<<p2<<endl;
 HufArry[p1].Parent = i;   //设置两颗最小树的双亲
 HufArry[p2].Parent = i;
 HufArry[i].Lchild = p1;   //设置这棵3节点的树的根的权值以及孩子
 HufArry[i].Rchild = p2;   
 HufArry[i].Weight = HufArry[p1].Weight + HufArry[p2].Weight;
 }
 cout<<"************************"<<endl;
}
void HufTree::SelectMin(int i,int &p1,int &p2)
{
 int least1 = MAXWEIGHT;
 int least2 = MAXWEIGHT;
 for(int j = 0; j < i; j++)
 {
 if(HufArry[j].Parent == -1)
 {
  
  if(HufArry[j].Weight < least1)
  {
  least2 = least1;
  least1 = HufArry[j].Weight;
  p2 = p1;
  p1 = j;
  }
  else
  {
  if(HufArry[j].Weight < least2)
  {
   least2 = HufArry[j].Weight;
   p2 = j;
  }
  }
 }
 }
}
void HufTree::Find_Root_and_Print()
{
 int root;
 for(int i = 0; i < HUFNUM - 1; i++)
 {
 if(HufArry[i].Parent == -1)
 {
  root = i;
  break;
 }
 }
 PrintHuf(root);
}
void HufTree::PrintHuf(int position)
{
 if(NodeNum == LEAFNUM)
 {
 
 return;
 }
 else
 {
 if(HufArry[position].Data != '\0') //如果是叶子节点
 {
  cout<<"权值:"<<HufArry[position].Weight<<"<-> 数据:"<<HufArry[position].Data<<" 此节点为叶子"<<endl;
  NodeNum = NodeNum + 1;
 }
 else
 {
  cout<<"权值:"<<HufArry[position].Weight<<" 此节点无数据域,不是叶子"<<endl;
  PrintHuf(HufArry[position].Lchild);
  PrintHuf(HufArry[position].Rchild);
 }
 }
 
  
}
int main()
{
 HufTree Tree;
 cout<<"请输入"<<LEAFNUM<<"对(权值,数据):"<<endl;
 double wei;
 char ch;
 for(int i = 0; i < LEAFNUM; i++)
 {
 cin>>wei;
 cin>>ch;
 Tree.SetHuf(i,wei,ch);
 }
 Tree.CreatHuf();     //创建哈夫曼树
 Tree.Find_Root_and_Print();           //遍历哈夫曼树
 return 0;
}

1 a
2 b
5 c
7 d
4 e
13 f
3 g
6 h
11 i
8 l