哈夫曼编码的设计与实现

#include <stdio.h>#define MAXVALUE 10000#define MAXLEAF 30#define MAXNODE 59#define MAXBIT 10//哈夫曼树结构typedef struct{    int data;   //结点值    int Weight; //权重    int Flag;   //标识是否待构节点，是的话用0表示，否则用1表示    int Parent; //父结点    int LChild; //左结点    int RChild; //右结点}hnodetype;typedef struct{    int Bit[MAXBIT];    int Start;}hcodetype;/****--------------------------------------------*****///函数名： InitHaffman(hnodetype HuffNode[], hcodetypde HuffNode[], int n)//参数：  (传入) hnodetype HuffNode[] 哈夫曼树结点//        (传入) hcodetype HuffCode[] 哈夫曼编码树结点//        (传入) int n 结点数量//功能:   哈夫曼结点初始化/****--------------------------------------------*****/void InitHaffman(hnodetype HuffNode[], hcodetype HuffCode[], int n){    int i;    //把生成的结点初始化,把指向父亲的指针,左孩子,右孩子的指针都先置空     for(i = 0; i < 2*n-1; i++) {        HuffNode[i].Weight = 0;        HuffNode[i].Parent = 0;        HuffNode[i].Flag = 0;        HuffNode[i].LChild = -1;        HuffNode[i].RChild = -1;     }     for(i = 0; i < n; i++) {        getchar();        printf("输入第%d个叶结点值:", i+1);        scanf("%c", &HuffNode[i].data);        printf("输入对应结点权值:");        scanf("%d", &HuffNode[i].Weight);     }}/****--------------------------------------------*****///函数名: OutputHaffman(hnodetype HuffNode[], hcodetype HuffNode[], int n)//参数名: (传入)hnodetype HuffNode[] 哈夫曼树结点//        (传入)hcodetype HuffNode[] 哈夫曼树编码树结点//        (传入)int n 结点数量//功能:   输出哈夫曼编码/****--------------------------------------------*****/void OutputHaffman(hnodetype HuffNode[], hcodetype HuffCode[], int n){    int i, j;    printf("%d个叶结点对应编码为:\n", n);    for(i = 0; i < n; i++) {        printf("%c- - - -",HuffNode[i].data);        for(j = HuffCode[i].Start+1; j < n; j++) {            printf("%d", HuffCode[i].Bit[j]);        }        printf("\n");    }}/****-------------------------------------------*****///函数名: Haffman(hnodetype HuffNode[], hcodetypeCode[], int n)//参数:   (传入)hnodetype HuffNode[]  哈夫曼树结点//        (传入)hcodetype HuffCode[] 哈夫曼树编码树结点//        (传入)int n 结点数量//功能:   构造哈夫曼树,根据树生成哈夫曼编码/****-------------------------------------------*****/void Haffman(hnodetype HuffNode[], hcodetype HuffCode[], int n){    int i, j, m1, m2, x1, x2, c, p;    hcodetype cd;    for(i = 0; i < n-1; i++) { //构造哈夫曼树       //根据哈夫曼树的构造过程,始终选择最小权值的两个结点构成一个二叉树       m1 = m2 = MAXVALUE;       //x1 和 x2位最小权重的两个结点位置       x1 = x2 = 0;       //循环从flag为0的节点中找到一个,供下面取最小值       for(j = 0; j < n+i; j++) {        if(HuffNode[j].Weight < m1 && HuffNode[j].Flag == 0) {            m2 = m1;            x2 = x1;            m1 = HuffNode[j].Weight;            x1 = j;  //记下x2的地址        }        else if(HuffNode[j].Weight < m2 && HuffNode[j].Flag == 0)        {            m2 = HuffNode[j].Weight;            x2 = j;        }       }//for        //把找到的两个节点按照哈夫曼树的规则构建成一个二叉树,x1为左孩子,x2为右孩子        HuffNode[x1].Parent = n+i;        HuffNode[x2].Parent = n+i;        HuffNode[x1].Flag = 1;  //将x1的下标置1        HuffNode[x2].Flag = 1;  //将x2的下标置1        HuffNode[n+i].Weight = HuffNode[x1].Weight + HuffNode[x2].Weight;        HuffNode[n+i].LChild = x1;        HuffNode[n+i].RChild = x2;    }//for    for(i = 0; i < n; i++) {//根据哈夫曼树生成哈夫曼编码        cd.Start = n-1;        c = i;        p = HuffNode[c].Parent;        while(p != 0) {//当父结点不为根结点的时候,逆序往上找            //如果当前是左孩子,则编码为0            if(HuffNode[p].LChild == c) cd.Bit[cd.Start] = 0;            //当前左孩子的编码为1            else cd.Bit[cd.Start] = 1;            cd.Start--;            c = p;            p = HuffNode[c].Parent;        }        for(j = cd.Start+1; j < n; j++) {            HuffCode[i].Bit[j] = cd.Bit[j];            HuffCode[i].Start = cd.Start;        }    }//for}//end of Haffmanint main(){    hnodetype HuffNode[MAXNODE];    hcodetype HuffCode[MAXLEAF];    int n;    printf("输入叶结点个数n:\n");    scanf("%d", &n);    InitHaffman(HuffNode, HuffCode, n);    Haffman(HuffNode, HuffCode, n);    OutputHaffman(HuffNode, HuffCode, n);    return 0;}