哈夫曼树编码

来源：互联网发布：全球最大域名注册商编辑：程序博客网时间：2024/04/28 08:39

由于建成树的随机性以及编码的随机性
文件的读入不能以ascii码形式读入

ascii码的读入方式会忽略掉一些流不能完整读入所以要用二进制码读入方式

下面是压缩的代码

#include<cstring>#include<cstdio>#include<cmath>#include<cstdlib>#include<iostream>using namespace std;struct heap{    int ele[22222];    int  e[22222];    int n;    heap(){n=0;}    int pre(int x){return (x-1)>>1;}    int lson(int x) {return (x<<1)+1;}    int rson(int x) {return (x<<1)+2;}    void ins(int  x,int  k)    {        int p=n++;        for(;p>0;)        {            if(ele[pre(p)]>x)            {                ele[p]=ele[pre(p)];e[p]=e[pre(p)];                p=pre(p);            }            else break;        }        ele[p]=x,e[p]=k;    }    int pop(int  &y)    {        int tmp,p,x=ele[0];y=e[0];        for(n--,p=0;lson(p)<n;)        {            tmp=(rson(p)<n&&ele[rson(p)]<ele[lson(p)])?rson(p):lson(p);            if(ele[tmp]<ele[n])  {ele[p]=ele[tmp];e[p]=e[tmp];p=tmp;}            else break;        }        ele[p]=ele[n];e[p]=e[n];        return x;    }}G;int n;int num[258];int next[513][2];bool yes[256][256];int len[256];bool ye[256];void dfs(int r,int k){    if(r<=256)    {        len[r]=k;        for(int i=0;i<k;++i)        yes[r][i]=ye[i];        return;    }   ye[k]=0; dfs(next[r][0],k+1);   ye[k]=1;dfs(next[r][1],k+1);}int main(){   FILE *p,*ps;   ps=fopen("data.txt","r");  p=fopen("data.out","wb");   n=0;   unsigned char c;   int l=0;   memset(num,0,sizeof(num));   while(fscanf(ps,"%c",&c)!=EOF)   {       num[(int)c]++;     //  printf("%d\n",(int) c);   }   for(int i=0;i<=256;++i)   if(num[i]!=0) G.ins(num[i],i),++n;   int y=256;   for(int i=0;i<n-1;++i)   {       int  t1,t2;       int x1,x2;       x1=G.pop(t1);x2=G.pop(t2);       ++y;       G.ins(x1+x2,y);       next[y][0]=t1;       next[y][1]=t2;   }     dfs(y,0);      unsigned char  q=0;int j=0;     for(int i=0;i<32;++i)     {         q+=((n&(1<<(i)))?(1<<(i%8)):0);         if(i%8==7) {fprintf(p,"%c",q);q=0;}     }     for(int i=0;i<=256;++i)     {        if(num[i]) {fprintf(p,"%c",(char)i);        for(int j=0;j<32;++j)     {         q+=(num[i]&(1<<(j)))?(1<<(j%8)):0;;         if(j%8==7) {fprintf(p,"%c",q);q=0;}     }     }     }     FILE *pp=fopen("data.txt","r");     q=0;     char sb;     while(fscanf(pp,"%c",&sb)==1)     {         int r=sb;         for(int k=0;k<len[r];++k,j=(j+1)%8)         {             q+=(1<<j)*yes[r][k];                if(j==7) {fprintf(p,"%c",(unsigned char )q);q=0;}         }     }   if((int)q!=0) fprintf(p,"%c",(unsigned char )q);    return 0;}

这个是解压的代码

#include<cstring>#include<cstdio>#include<cmath>#include<cstdlib>#include<iostream>using namespace std;struct heap{    int ele[22222];    int  e[22222];    int n;    heap(){n=0;}    int pre(int x){return (x-1)>>1;}    int lson(int x) {return (x<<1)+1;}    int rson(int x) {return (x<<1)+2;}    void ins(int  x,int  k)    {        int p=n++;        for(;p>0;)        {            if(ele[pre(p)]>x)            {                ele[p]=ele[pre(p)];e[p]=e[pre(p)];                p=pre(p);            }            else break;        }        ele[p]=x,e[p]=k;    }    int pop(int  &y)    {        int tmp,p,x=ele[0];y=e[0];        for(n--,p=0;lson(p)<n;)        {            tmp=(rson(p)<n&&ele[rson(p)]<ele[lson(p)])?rson(p):lson(p);            if(ele[tmp]<ele[n])  {ele[p]=ele[tmp];e[p]=e[tmp];p=tmp;}            else break;        }        ele[p]=ele[n];e[p]=e[n];        return x;    }}G;int n;int num[258];int next[514][2];int fseek(FILE * in){    int res=0;    int i=0;    for(int j=0;j<4;++j)    {        unsigned char k;        fscanf(in,"%c",&k);        for(int y=0;y<8;++y,++i)        if(k&(1<<y)) res+=(1<<i);    }    return res;}int main(){    FILE *p;    p=fopen("data.out","rb"); //freopen("data1.txt","w",stdout);unsigned char c;   int l=0;   memset(num,0,sizeof(num));  int ks=0;  n=fseek(p);  for(int i=0;i<n;++i)  {      int t;      fscanf(p,"%c",&c);     t=fseek(p);      l+=t;      G.ins(t,(int)c);      }   int y=256;   for(int i=0;i<n-1;++i)   {       int  t1,t2;       int x1,x2;       x1=G.pop(t1);x2=G.pop(t2);       ++y;       G.ins(x1+x2,y);       next[y][0]=t1;       next[y][1]=t2;   }   int temp=y;   int nu=0; unsigned char sb;   int xx=0;  // cout<<l<<endl;   while(l)   {       fscanf(p,"%c",&sb);       int s=(int) sb;     for(int i=0;i<8&&l;++i)       {           temp=next[temp][(s&(1<<i))==0?0:1];           if(temp<=256) {putchar((char)temp);++xx;temp=y;--l;}       }   }  // cout<<endl<<l<<" "<<xx<<endl;    return 0;}

-。-由于编码方式的问题暂时不支持中文的压缩的