霍夫曼树编码的实现

    　　#include <stdio.h>
    #include <stdlib.h>
    #include <string.h>
    #include <conio.h>

    typedef strUCt
    {
        unsigned int Weight;
        unsigned int Parent;
        unsigned int lChild;
        unsigned int rChild;
    }HTNode,*HuffmanTree;

    typedef char **HuffmanCode;

    int LookFor(char *str,char letter,int count);
    void OutputWeight(char *Data,int Length,
                      char **WhatLetter,
                      int **Weight,int *Count);
    void HuffmanCoding(HuffmanTree *HT,
                       HuffmanCode *HC,
                       int *Weight,
                       int Count);
    void Select(HuffmanTree HT,int Count,int *s1,int *s2);
    int main()
    {
        HuffmanTree HT;
        HuffmanCode HC;
        char Data[100];
        char *WhatLetter;
        int *Weight;
        int Count;
        int i;

        printf("Please input the line:");
        /* Example: aaaaaaaaaaaaaabcccccc*/
       scanf("%s",Data);
        printf("\n");

        OutputWeight(Data,strlen(Data),
                     &WhatLetter,
                     &Weight,
                     &Count);

        HuffmanCoding(&HT,&HC,Weight,Count);

        printf(" Letter Weight Code\n");
        for(i=0;i<Count;i++)
        {
            printf(" %c ",WhatLetter[i]);
            printf("%d ",Weight[i]);
            printf("%s\n",HC[i+1]);
        }
        printf("\n");
        getch();
        return 0;
    }

    void HuffmanCoding(HuffmanTree *HT,
                       HuffmanCode *HC,
                       int *Weight,
                       int Count)
    {
        int i;
        int s1,s2;
        int TotalLength;
        HuffmanTree p;
        char* cd;

       unsigned int c;
        unsigned int f;
        int start;

        if(Count<=1) return;
        TotalLength=Count*2-1;
        (*HT)=(HuffmanTree)malloc((TotalLength+1)*sizeof(HTNode));

        p=((*HT)++);
        for(i=1;i<=Count;i++)
        {
            (*HT)[i].Parent=0;
            (*HT)[i].rChild=0;
            (*HT)[i].lChild=0;
            (*HT)[i].Weight=(*Weight);
            Weight++;
        }
        for(i=Count+1;i<=TotalLength;i++)
        {
            (*HT)[i].Weight=0;
            (*HT)[i].Parent=0;
            (*HT)[i].lChild=0;
            (*HT)[i].rChild=0;
        }
        /*///////////////////Create HuffmanTree////////////////*/
        for(i=Count+1;i<=TotalLength;++i)
        {
            Select((*HT),i-1,&s1,&s2);
           (*HT)[s1].Parent=i;
           (*HT)[s2].Parent=i;
           (*HT)[i].lChild=s1;
           (*HT)[i].rChild=s2;
           (*HT)[i].Weight=(*HT)[s1].Weight+(*HT)[s2].Weight;
       }
        /*///////////////////Output Huffman Code///////////////*/
        (*HC)=(HuffmanCode)malloc((Count+1)*sizeof(char*));
        cd=(char*)malloc(Count*sizeof(char));
        cd[Count-1]='\0';
        for(i=1;i<=Count;++i)
        {
            start=Count-1;
            for(c=i,f=(*HT)[i].Parent;f!=0;c=f,f=(*HT)[f].Parent)
            {
                if((*HT)[f].lChild==c)
                    cd[--start]='0';
                else
                    cd[--start]='1';
                (*HC)[i]=(char*)malloc((Count-start)*sizeof(char));
                strcpy((*HC)[i],&cd[start]);
            }
        }
    }
    void Select(HuffmanTree HT,int Count,int *s1,int *s2)
    /*/(*s1) is smallest,(*s2) is smaller.*/
    {
        int i;
        unsigned int temp1=0;
        unsigned int temp2=0;
        unsigned int temp3;
        for(i=1;i<=Count;i++)
        {
            if(HT[i].Parent==0)
          {
                if(temp1==0)
                {
                   &