程序代码：

#include "iostream.h"
#include "malloc.h"
#include "string.h"
#define MAXSIZE 30
#define MAX 100

typedef struct 
{
    char data;
    int weight;
    int parent;
    int left;
    int right;
}HTNode, *HuffmanTree;

typedef char **HuffmanCode;

typedef struct 
{
    char data;
    int weight;
}Tdata;

HuffmanTree HT;
HuffmanCode HC;
void SelectMinTree(HuffmanTree HT,int n,int *s1,int *s2);
void HuffmanCoding(HuffmanTree HT,Tdata *w,int n);

void SelectMinTree(HuffmanTree HT,int n,int *s1,int *s2)
{
    int i,min1,min2;
    *s2=*s1=0;
    min1=min2=MAX;
    for(i=1;i<=n;i++)
    {
        if (HT[i].parent==0)
            if (HT[i].weight<min1)
            {
                min2=min1;
                min1=HT[i].weight;
                *s2=*s1;
                *s1=i;
            }
        else
            if (HT[i].weight<min2)
            {
                min2=HT[i].weight;
                *s2=i;
            }
    }
}

void HuffmanCoding(HuffmanTree HT,Tdata *w,int n)
{
    int m,i,s1,s2,start,c,f;
    HTNode *p;
    char *cd;
    if(n<=1)return;
    m=2*n-1;
    HT=(HuffmanTree)malloc((m+1)*sizeof(HTNode));
    for(p=HT+1,i=1;i<=n;i++,p++)
    {
        p->data=w[i].data;
        p->weight=w[i].weight;
        p->left=0;
        p->right=0;
        p->parent=0;
    }
    for(;i<=m;i++,p++)
    {
        p->weight=0;
        p->left=0;
        p->right=0;
        p->parent=0;
    }
    for(i=n+1;i<=m;i++)
    {
        SelectMinTree(HT,i-1,&s1,&s2);
        HT[s1].parent=i;HT[s2].parent=i;
        HT[i].left=s1;HT[i].right=s2;
        HT[i].weight=HT[s1].weight+HT[s2].weight;
    }
    HC=(HuffmanCode)malloc((n+1)*sizeof(char *));
    cd=(char *)malloc(n*sizeof(char));
    cd[n-1]='\0';
    for(i=1;i<=n;i++)
    {
        start=n-1;
        for(c=i,f=HT[i].parent;f!=0;c=f,f=HT[f].parent)
            if (HT[f].left==c)
                cd[--start]='0';
            else
                cd[--start]='1';
        HC[i]=(char *)malloc((n-start)*sizeof(char));
        strcpy(HC[i],&cd[start]);
    }
    free(cd);
}

void main()
{
    Tdata w[MAXSIZE];
    int n,i;
    cout<<"请输入元素数：";
    cin>>n;
    for(i=1;i<=n;i++)
    {
        cout<<"input"<<i<<"data name and weight:";
        cin>>w[i].data>>w[i].weight;
    }
    cout<<"*************result*************"<<endl;
    HuffmanCoding(HT,w,n);
    for(i=1;i<=n;i++)
        cout<<w[i].data<<"----------->"<<HC[i]<<endl;
}