赫夫曼编译码器实验报告

#include<stdio.h>
#include<stdlib.h>
#include<string.h>
#include<math.h>
#define MAX 100
#define MAXVALUE 10000

typedef struct{
    char ch;
    int weight,flag;
    int parent,lchild,rchild;
}HTNode;

typedef struct{
    char ch;
    int bit[MAX];
    int start,weight;
}Code;

typedef struct{
    char ch;
    char bit[MAX];
    int weight;
}Coding;

void HaffmanCoding1(int weight[],char ch[],int n,HTNode haffTree[]){
    /**
    生成哈夫曼树的函数1
    */
    int i,j,m1,m2,x1,x2;
    for (i=0;i<2*n-1;i++){
       if(i<n){
           haffTree[i].weight=weight[i];
           haffTree[i].ch=ch[i];
       }
       else haffTree[i].weight=0;
       haffTree[i].parent=-1;
       haffTree[i].flag=0;
       haffTree[i].lchild=-1;
       haffTree[i].rchild=-1;
    }
    for (i=0;i<n-1;i++){
       m1=m2=MAXVALUE;
       x1=x2=0;
       for (j=0;j<n+i;j++){
           if (haffTree[j].weight<m1&&haffTree[j].flag==0){
              m2=m1;
              x2=x1;
              m1=haffTree[j].weight;
              x1=j;
           }
           else if(haffTree[j].weight<m2 && haffTree[j].flag==0){
              m2=haffTree[j].weight;
              x2=j;
           }
       }
       haffTree[x1].parent= n + i;
       haffTree[x2].parent = n + i;
       haffTree[x1].flag = 1;
       haffTree[x2].flag = 1;
       haffTree[n+i].weight = haffTree[x1].weight + haffTree[x2].weight;
       haffTree[n+i].lchild = x1;
       haffTree[n+i].rchild = x2;
    }
    /**
    把哈弗曼树存储到huffman.txt中。
    */
    FILE *fp;
    fp=fopen("huffman.txt","w+");
    printf("%d\n",n);
    fprintf(fp,"%d\n",n);
    for (i=0;i<n;i++)
       fprintf(fp,"%c %d %d %d\n",haffTree[i].ch,haffTree[i].parent,haffTree[i].lchild,haffTree[i].rchild);
    for (i=n;i<2*n-1;i++)
       fprintf(fp,"%d %d %d\n",haffTree[i].parent,haffTree[i].lchild,haffTree[i].rchild);
    fclose(fp);
}

void HaffmanCoding2(HTNode haffTree[],int n,Code haffCode[]){
    /**
    生成哈夫曼树的函数2
    */
    Code *cd=( Code *) malloc (sizeof (Code));
    int i,j,child,parent;
    for (i=0; i<n; i++){
       cd->start=n-1;
       cd->weight=haffTree[i].weight;
       cd->ch=haffTree[i].ch;
       child=i;
       parent=haffTree[child].parent;
       while (parent !=-1){
           if (haffTree[parent].lchild==child)
              cd->bit[cd->start]=0;
           else
              cd->bit[cd->start]=1;
           cd->start--;
           child =parent;
           parent=haffTree[child].parent;
       }
       for (j=cd->start+1; j<n; j++)
           haffCode[i].bit[j]=cd->bit[j];
       haffCode [i].start = cd->start+1;
       haffCode [i].weight=cd->weight;
       haffCode [i].ch=cd->ch;
    }
}

void Initialization(int weight[],char ch[]){
    /**
    构造n个字符的赫夫曼编码HC
    */
    FILE *fp;
    int i,j,n;
    char ch1,wj[15];
    printf("系统正在初始化。。。\n请输入字符集大小n:\n");
    scanf("%d",&n);
    HTNode *myHaffTree=(HTNode *)malloc(sizeof (HTNode)*(2*n+1));
    Code *myHaffCode =(Code *)malloc (sizeof (Code)*n);
    for (i=0;i<n;i++){
        printf("请输入字符和权值:\n");
        getchar();
        ch[i] = getchar();
        scanf("%d",&weight[i]);
    }
    HaffmanCoding1(weight,ch,n,myHaffTree);
    HaffmanCoding2(myHaffTree,n,myHaffCode);
    fp=fopen("hfmTree.txt","w+");
    for (i=0;i<n;i++){
       printf("%c %d ",myHaffCode[i].ch,myHaffCode[i].weight);
       fprintf(fp,"%c %d ",myHaffCode[i].ch,myHaffCode[i].weight);
        for ( j=myHaffCode[i].start; j<n; j++){
           printf("%d",myHaffCode[i].bit[j]);
           fprintf(fp,"%d",myHaffCode[i].bit[j]);
       }
            fprintf(fp,"\n");
       printf("\n");
    }
    fclose(fp);
    printf("初始化成功!\n");
}

void Encoding(){
    /**
    利用以建好的哈弗曼树(如不存在，从文件hfmTree中读)
    输入正文进行编码，然后将结果存入文件CodeFile中
    */
    FILE *fp,*fp1,*fp2;
    char zf[500];
    fp=fopen("hfmTree.txt","r");
    Coding ch[100];
    char c;
    int i=0;
    while (feof(fp)==0){
           fscanf(fp,"%s %d %s",&ch[i].ch,&ch[i].weight,&ch[i].bit);
            i++;
    }
    fclose(fp);
    printf("现在进行编码操作。。。\n请输入字符串:\n");
    scanf("%s",zf);
    char ch1[20],ch2[20];
    int j;
    fp2=fopen("CodeFile.txt","w+");
    int len,k;
    len=strlen(zf);
    for (k=0; k<len; k++)
        for (j=0; j<i; j++)
            if (ch[j].ch==zf[k]){
                fprintf(fp2,"%s",ch[j].bit);
                printf("%s",ch[j].bit);
            }
    printf("\n");
    fclose(fp2);
    printf("编码完成!已将结果存入CodeFile.txt中.\n\n");
}

void Decoding(){
    /**
    利用已建好的哈弗曼树将文件CodeFile中的代码进行译码，结果存入文件TextFile中。
    */
    FILE *fp,*fp1;
    fp=fopen("huffman.txt","r");
    int i,n;
    fscanf(fp,"%d",&n);
    HTNode *myHaffTree=(HTNode *)malloc(sizeof (HTNode)*(2*n+1));
    for (i=0;i<n;i++)
        fscanf(fp,"%s %d %d %d\n",&myHaffTree[i].ch,&myHaffTree[i].parent,&myHaffTree[i].lchild,&myHaffTree[i].rchild);
    for (i=n;i<2*n-1;i++)
       fscanf(fp,"%d %d %d\n",&myHaffTree[i].parent,&myHaffTree[i].lchild,&myHaffTree[i].rchild);
    fclose(fp);
    fp=fopen("CodeFile.txt","r");
    fp1=fopen("TextFile.txt","w+");
    char ch;
    i=2*n-2;
    while (!feof(fp)){
        fscanf(fp,"%c",&ch);
       if (ch=='0') i=myHaffTree[i].lchild;
       if (ch=='1') i=myHaffTree[i].rchild;
       if (i<n){
           printf("%c",myHaffTree[i].ch);
            fprintf(fp1,"%c",myHaffTree[i].ch);
           i=2*n-2;
       }
    }
    printf("\n");
    fprintf(fp1,"\n");
    fclose(fp);
    fclose(fp1);
    printf("译码过程完成!已将结果存入TextFile.txt中.\n\n");
}

void Print(){
    /**
    将文件CodeFile以紧凑格式显示在终端上，每行50个代码
    同时将此字符形式的编码文件写入文件CodePrin中。
    */
    FILE *fp1,*fp2;
    fp1=fopen("CodeFile.txt","r");
    fp2=fopen("CodePrin.txt","w+");
    int count=0;
    char ch;
    while (!feof(fp1)){
        fscanf(fp1,"%c",&ch);
       printf("%c",ch);
       fprintf(fp2,"%c",ch);
       count++;
       if (count==50){
           printf("\n");
           fprintf(fp2,"\n");
            count=0;
       }
    }
    printf("\n");
    fprintf(fp2,"\n");
    fclose(fp1);
    fclose(fp2);
    printf("打印代码过程完成!已将结果存入CodePrin.txt中.\n\n");

}

void PrintTree(HTNode *huf,int n,int p,FILE *fp)
{
    /**
    打印哈弗曼树函数
    树是横向显示的，叶子节点显示字符，非叶子节点显示'@'
    */
    int i;
    if (n==-1)  return;
    PrintTree(huf,huf[n].rchild,p+1,fp);
    for (i=0;i<p;i++){
        printf("   ");
        fprintf(fp,"   ");
    }
    if (p>=0&&huf[n].rchild==-1){
       printf("---");
       printf("%c\n",huf[n].ch);
       fprintf(fp,"---%c\n",huf[n].ch);
    }
    else{
       printf("@\n");
       fprintf(fp,"@\n");
    }
    PrintTree(huf,huf[n].lchild,p+1,fp);
}

void Treeprinting(){
     /**
    将已在内存中的哈弗曼树以直观的方式(树或凹入表形式)显示在终端上
    同时将次字符形式的哈弗曼树写入文件TreePrint中。
    */
    FILE *fp;
    fp=fopen("huffman.txt","r");
    int i,n;
    fscanf(fp,"%d",&n);
    HTNode *myHaffTree=(HTNode *)malloc(sizeof (HTNode)*(2*n+1));
    for (i=0;i<n;i++)
       fscanf(fp,"%s %d %d %d\n",&myHaffTree[i].ch,&myHaffTree[i].parent,&myHaffTree[i].lchild,&myHaffTree[i].rchild);
    for (i=n;i<2*n-1;i++)
       fscanf(fp,"%d %d %d\n",&myHaffTree[i].parent,&myHaffTree[i].lchild,&myHaffTree[i].rchild);
    fclose(fp);
    fp=fopen("TreePrint.txt","w+");
    PrintTree(myHaffTree,2*n-2,0,fp);
    fclose(fp);
    printf("打印哈夫曼树过程完成!同时已将结果存入TreePrint中.\n\n");
}

void Menuprint(){
    printf("*******************************************************************************\n");
    printf("*****                                                                     *****\n");
    printf("*****                                                                     *****\n");
    printf("*****                       欢迎使用哈夫曼编／译码器                      *****\n");
    printf("*****                                                                     *****\n");
    printf("*****                                                                     *****\n");
    printf("***** E.编码　　　D.译码　　　P.印代码文件　　　T.印哈夫曼树　　　Q.退出  *****\n");
    printf("*****                                                                     *****\n");
    printf("*******************************************************************************\n");
}

int main()
{
    int i,j,n=4;
    int weight[100];
    char ch[100],cha;
    Menuprint();
    Initialization(weight,ch);
    while (1){
      printf("请输入要执行的操作:\nE.编码　　　D.译码　　　P.印代码文件　　　T.印哈夫曼树　　　Q.退出\n");
       printf("请输入要执行的操作:\n");
       scanf("%s",&cha);

       if (cha=='Q')    break;

       switch (cha){
       case 'E':    Encoding();     break;
       case 'D':    Decoding();     break;
       case 'P':    Print();        break;
       case 'T':    Treeprinting(); break;
       }
    }
    return 0;
}