数据结构哈夫曼编码(源代码)

#include

#include

#include

#include

#define N 1000

char kind[N]={'\0'};

int num[N]={0};

int count=0;

int s1,s2;

typedef struct

{

int weight; /*字符权重*/

int parent,lchild,rchild;

}HTNode,*HuffmanTree; /*定义哈夫曼树结点*/ typedef char **HuffmanCode;

struct charcode

{

char data;

char code[20];

}Code[N],d[N],e[N];

void Creat_message() /*输入字符并存入文件*/

{

FILE *fp;

char c;

if((fp=fopen("文本文件.txt","wb"))==NULL)

{

printf("cannot open this file!\n");

return ;

}

printf("请输入原代码，以'#'表示结束\n");

do{

scanf("%c",&c);

fputc(c,fp);

}while (c!='#');

fclose(fp);

}

void Calculate() /*计算文件中字符的权值*/ {

char c;

int i=1,k;

FILE *fp;

if((fp=fopen("文本文件.txt","rb"))==NULL){

printf("cannot open this file\n");

return ;

}

c=fgetc(fp);

while(c!='#'){

for (k=0;k

if(c==kind[k]){

num[k]++;break;}

if(k>=i&&kind[k-1]!=c){

kind[i]=c;num[i]++;i++;

}

c=fgetc(fp);

}

count=i-1;

}

void select(HuffmanTree Hu,int j) /*寻找输入的字符数据中权值最小的两个结点*/ {

int k=1,t;

while(Hu[k].parent!=0) k++;

for(t=k;t<=j;t++)

if(Hu[t].parent==0 && Hu[t].weight

k=t;

s1=k;

k=1;

while(Hu[k].parent!=0 ||k==s1) k++;

for(t=k;t<=j;t++)

if(Hu[t].weight

k=t;

s2=k;

}

void HuffmanCoding () /*构建哈夫曼树并编码*/

{

void select(HuffmanTree Hu,int j);

HuffmanTree HT;

HuffmanCode HC;

int m,i,start,f,c;

char *cd;

FILE *fp;

if (count<=1) return;

m=2*count-1;

HT=(HuffmanTree)malloc((m+1)*sizeof(HTNode));

for(i=1;i<=count;i++)

HT[i].weight=num[i];

for(i=1;i<=m;i++){

HT[i].parent=0;

HT[i].lchild=0;

HT[i].rchild=0;}

for(i=count+1;i<=m;i++){

select(HT,i-1);

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;} 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]);}

if((fp=fopen("字符代码.txt","wb"))==NULL)

{

printf("cannot open this file\n");

return ;

}

for(i=1;i<=count;i++){

Code[i].data= kind[i];

strcpy(Code[i].code,HC[i]);

fwrite(&Code[i],sizeof(struct charcode),1,fp);

}

fclose(fp);

}

void Transform() /*将字符文件翻译成代码文件*/ {

FILE *fp1,*fp2,*fp3;

int i;

char c;

if((fp1=fopen("字符代码.txt","rb"))==NULL){

printf("cannot open this file\n");

return ;

}

if((fp2=fopen("文本文件.txt","rb"))==NULL){

printf("cannot open this file\n");

return ;

}

if((fp3=fopen("码本文件.txt","wb"))==NULL){

printf("cannot open this file\n");

return ;

}

for(i=0;i

fread(&d[i],sizeof(struct charcode),1,fp1);

while(!feof(fp2)){

c=fgetc(fp2);

for(i=0;i

if(d[i].data==c){

fputs(d[i].code,fp3);

break;}

}

fputc('#',fp3);

fclose(fp3);

}

void Translate() /*将代码文件翻译成字符文件*/ {

FILE *fp1,*fp2,*fp3;

int i,j,k;

char c[20]={'\0'};

if((fp1=fopen("码本文件.txt","rb"))==NULL){ printf("cannot open this file\n");

return ;

}

if((fp2=fopen("字符代码.txt","rb"))==NULL){ printf("cannot open this file\n");

return ;

}

if((fp3=fopen("破译文件.txt","wb"))==NULL){ printf("cannot open this file\n");

return ;

}

for(i=1;i<=count;i++)

fread(&d[i],sizeof(struct charcode),1,fp2);

i=0;

c[i]=fgetc(fp1);

while(c[i]!='#'){

for(k=1;k<=count;k++)

if(!strcmp(c,d[k].code)){

fputc(d[k].data,fp3);

for(j=0;j<=i;j++) c[j]='\0';

i=-1;

break;

}

i++;

c[i]=fgetc(fp1);

}

fputc('#',fp3);

fclose(fp1);

fclose(fp2);

fclose(fp3);

}

void print1(char *name) /*打印文件函数*/ {

FILE *fp;

char c;

if((fp=fopen(name,"rb"))==NULL){

printf("cannot open this file\n");

return ;

}

c=fgetc(fp);

while(c!='#'){

printf("%c",c);

c=fgetc(fp);

}

}

void print2(char *name) /*打印文件函数*/ {

FILE *fp;

int i=1;

if((fp=fopen(name,"rb"))==NULL){

printf("cannot open this file\n");

return ;

}

while(!feof(fp)){

fread(&e[i],sizeof(struct charcode),1,fp);

printf("%c--%s\n",e[i].data,e[i].code);

i++;

}

}

void main()

{

Creat_message();

printf("您输入的文本文件是：\n");

print1("文本文件.txt");

printf("\n");

Calculate();

HuffmanCoding ();

printf("每个字符相应的哈夫曼编码是：\n");

print2("字符代码.txt");

printf("\n");

Transform();

printf("原文件的码本文件（即全为字符编码）为:\n");

print1("码本文件.txt");

printf("\n");

Translate();

printf("用码本文件和字符代码求出的破译文件为:\n");

print1("破译文件.txt");

printf("\n");

}