algorithm-in-python/dataStructure/huffman/huffman.cc
2019-01-31 12:09:46 +08:00

376 lines
10 KiB
C++

/* mbinary
#########################################################################
# File : huffman.cc
# Author: mbinary
# Mail: zhuheqin1@gmail.com
# Blog: https://mbinary.xyz
# Github: https://github.com/mbinary
# Created Time: 2018-04-25 22:32
# Description:
#########################################################################
*/
#include<math.h>
#include<stdio.h>
#include<iostream>
#include<algorithm>
#include<map>
#include<unistd.h>
#include<iomanip>
#include<string>
#include<vector>
#include<queue>
#include<sys/time.h>
#define numDigit 10
#define nameLength 50
#define starNum 80
using namespace std;
void cat(string s)
{
FILE* f=fopen(s.c_str(),"rb");
cout<<"file content"<<endl;
while(!feof(f)){
cout<<fgetc(f);
}
cout<<endl;
}
string uniFileName(string file)
{
FILE * check = fopen(file.c_str(),"rb");
if(check){
char c;
cout<<"the file "<<file<<" already exists! continue? [Y/n]:"<<flush;
c=cin.get();
if(c=='n')exit(0);
int p,q;
p= file.find('(');
q=file.rfind('.');
if(q==string::npos)q=file.size();
if(p==string::npos)p=q;
string name=file.substr(0,p),suffix=file.substr(q,file.size());
int n=0;
while(true){
char s[3];
n+=1;
snprintf(s,3,"%d",n);
file=(name+"("+s+")"+suffix);
FILE* f=fopen(file.c_str(),"rb");
if(!f)break;
else fclose(f);
}
}
return file;
}
template<class t1, class t2>
void mapprint(map<t1,t2> &f)
{
for(class map<t1,t2>::iterator i = f.begin();i!=f.end();++i)
cout<<i->first<<") : "<<i->second<<endl;
}
template<typename ky,typename wt>
class node
{
public:
ky key;
wt val;
bool visited;
node * left,*right;
node(const node &a){val = a.val;key= a.key;visited = a.visited;left= a.left;right=a.right;}
node(ky k=0,wt v=0):key(k),val(v),visited(false),left(NULL),right(NULL){};
bool operator<(const node<ky,wt> & a)const{return val>a.val;};
};
template<typename ky,typename wt>
class huffman
{
private:
node<ky,wt> root;
string res;
public:
long total(){return root.val;}
map<ky,string> encode_map;
map<string,ky> decode_map;
huffman(map<ky,wt>& mp);
void display();
string encode(string,long &);
string decode(string,long&);
void preOrder(node<ky,wt>*,string);
};
template<typename ky,typename wt>
huffman<ky,wt>::huffman(map<ky,wt>& mp)
{
if(mp.empty()){
cout<<"Error! No data!"<<endl;
root=NULL;
return ;
}
priority_queue<node<ky,wt> > hp;
for(typename map<ky,wt>::iterator i=mp.begin();i!=mp.end();++i){
hp.push( node<ky,wt>(i->first,i->second));
}
int n =hp.size();
if(n==1){
root = hp.top();
return;
}
while(--n>=1){
node<ky,wt> *a = new node<ky,wt>(hp.top());
hp.pop();
node<ky,wt> *b = new node<ky,wt>(hp.top());
hp.pop();
node<ky,wt> * tmp = new node<ky,wt>(0,a->val+b->val);
tmp->left = a,tmp->right = b;
hp.push(*tmp);
}
root = hp.top();
preOrder(&root,string());
}
template<typename ky,typename wt>
void huffman<ky,wt>::preOrder(node<ky, wt>* nd,string s)
{
if(nd->left == NULL){
encode_map[nd->key] =s;
decode_map[s] = nd->key;
delete nd;
return ;
}
preOrder(nd->left,s+'0');
preOrder(nd->right,s+'1');
delete nd;
}
template<typename ky,typename wt>
string huffman<ky,wt>::decode(string zipfile_name,long &charNum)
{
string uniFileName(string);
FILE * src = fopen(zipfile_name.c_str(),"rb");
char file_name[nameLength];
fgets(file_name,nameLength,src);
int ct=-1;
while(file_name[++ct]!='\n');
int pos = zipfile_name.find('.');
if(pos==string::npos)pos=zipfile_name.size();
string name(zipfile_name.substr(0,pos)) ,suffix(file_name,file_name+ct),file(name+suffix);
file=uniFileName(file);
cout<<"extracting compressed file :"<<zipfile_name<<endl;
FILE * f = fopen(file.c_str(),"wb");
char t[numDigit];
fgets(t,numDigit,src);
int sz=atoi(t);
char code[sz];
fread(code,sz,1,src);
int idx=0;
for(int i =0;i<sz;++i ){
if(code[i]==' '){
decode_map[string(code+idx,code+i)]=code[++i];
idx=i+1;
}
}
for(int i=0;i<starNum;++i)cout<<"@";
cout<<endl;
char c;
long cur=charNum,gap=charNum/starNum;
while(cur){
c=fgetc(src);
if(!((--cur)%gap))cout<<"@"<<flush;
for(int i =0;i<8;++i){
if(c&(1<<i))res.append(1,'1');
else res.append(1,'0');
if(decode_map.count(res)!=0){
fputc(decode_map[res],f);
res.clear();
}
}
}
cout<<endl;
c=fgetc(src);
int dgt=fgetc(src);
cout<<feof(f);
if((int)dgt!=-1 ){
for(int i =0;i<dgt;++i){
if(c&(1<<i))res.append(1,'1');
else res.append(1,'0');
if(decode_map.count(res)!=0){
fputc(decode_map[res],f);
res.clear();
break;
}
}
}
fclose(src);
fclose(f);
cout<<"get "<<file <<" successfully"<<endl;
return file;
}
template<typename ky,typename wt>
string huffman<ky,wt>::encode(string file_name,long &charNum)
{
charNum=0;
string uniFileName(string);
int pos =file_name.rfind('.');
if(pos==string::npos)pos=file_name.size();
string zipfile = file_name.substr(0,pos)+string(".zzip");
zipfile = uniFileName(zipfile);
cout<<"generating zip file :"<<zipfile<<endl;
FILE * dst = fopen(zipfile.c_str(),"wb");
FILE * f = fopen(file_name.c_str(),"rb");
fputs(file_name.substr(pos).c_str(),dst);
fputc('\n',dst);
string data;
for(class map<string,ky>::iterator i=decode_map.begin();i!=decode_map.end() ;++i ){
data.append((i->first));
data.append(" ");
data+=(i->second);
}
int data_size = data.size(); // calculate the size of the code_data
char sz[numDigit];
snprintf(sz,numDigit,"%d",data_size);
int ct=0;
for(;sz[ct];++ct)fputc(sz[ct],dst);
fputc('\n',dst);
fwrite(data.c_str(),data_size,1,dst);
int sum=0,digit=0,num;
string code8;
for(int i=0;i<starNum;++i)cout<<"@";
cout<<endl;
long gap=root.val/starNum,cur=0;
while(!feof(f)){
code8=encode_map[fgetc(f)];
if(!((++cur)%gap))cout<<"@";
for(int i=0;i<code8.size();++i){
if(code8[i]=='1')sum += 1<<(digit); //mistake if(tmp[j])
++digit;
if(digit==8){
++charNum;
fputc(sum,dst);
digit=sum=0;
}
}
}
cout<<endl;
if(digit!=0){ //mark
fputc(sum,dst);
fputc(digit,dst);
}
fclose(f);
fclose(dst);
cout<<"compress "<<file_name <<" successfully"<<endl;
return zipfile;
}
template<typename ky,typename wt>
void huffman<ky,wt>::display()
{
cout<<"the encoding map,huffman codes are as bellow:"<<endl;
for (typename map<ky,string>::iterator i=encode_map.begin();i!=encode_map.end() ;++i )
cout<<i->first<<"("<<(int)i->first<<"):"<<i->second<<endl;
}
bool handle_one(string file_name,vector<long> &origin,vector<long> &compressed)
{
int name_length = file_name.size();
FILE *src=fopen(file_name.c_str(),"rb");
cout<<"opening "<<file_name<<"..."<<endl;
if(!src){
cout<<"Path Error! Opening "<<file_name<<" Failed"<<endl;
origin.push_back(0);
compressed.push_back(0);
return false;
}
char cur;
map<char,long> mp;
while(!feof(src)){
fread(&cur,sizeof(char),1,src);
if(mp.count(cur)){
mp[cur]+=1;
}
else mp[cur]=1;
}
fclose(src);
huffman<char,long> hf(mp);
long sz;
string s(hf.encode(file_name,sz));
origin.push_back(hf.total()),compressed.push_back(sz);
cout<<"\ncontinue to uncompress? [Y/n]"<<endl;
char c=cin.get();
if(c=='n')return true;
hf.decode(s,sz);
return true;
}
bool isSep(char c)
{
return c==' '||c=='\n'||c=='\t'||c==',';
}
void splitToVec(char * s,vector<string>& v)
{
int i=0,last=0;
for(;s[i];++i){
if(isSep(s[i])){
v.push_back(string(s+last,s+i));
while(s[++i]&&isSep(s[i]));
last=i;
}
}
if(s[last])v.push_back(string(s+last,s+i));
}
bool lenStr(string &a,string &b)
{
return a.size()<b.size();
}
void go(vector<string> & names)
{
vector<long> originSize,compressedSize;
vector<int> deltaTime;
double last;
vector<bool> indicator;
bool bl;
for(vector<string>::iterator i=names.begin();i!=names.end();++i){
struct timeval tv;
gettimeofday(&tv,NULL);
last=tv.tv_sec;
bl=handle_one(*i,originSize,compressedSize);
indicator.push_back(bl);
gettimeofday(&tv,NULL);
deltaTime.push_back(tv.tv_sec-last);
}
cout<<"\nDealt file number "<<originSize.size()<<fixed<<setprecision(2)<<endl;
vector<string>::iterator p=max_element(names.begin(),names.end(),lenStr);
int len = p->size()+2;
for(int i =0;i<names.size();++i){
if(! indicator[i]){continue;}
cout<<names[i]<<string(len-names[i].size(),' ');
cout<<deltaTime[i]<<"s "<<compressedSize[i]/1024.0<<"KB/"<<originSize[i]/1024.0<<"KB :";
cout<<compressedSize[i]*100.0/originSize[i]<<"%"<<endl;
}
cout<<endl;
system("pause");
}
int main(int argv,char ** argc)
{
char cwd[50];
cout<<getcwd(cwd,50)<<endl;
vector<string> names;
string file;
if(argv>1){
for(int i=1;i<argv;++i){
names.push_back(argc[i]);
}
go(names);
names.clear();
}
char mk;
while(1){
char s[201];
cout<<"Input file names separated by space "<<endl;
if(cin.peek()=='\n')names.push_back(file);
else {
cin.getline(s,200);
splitToVec(s,names);
}
cout<<endl;
go(names);
cout<<"Continue? [Y/n]:"<<flush;
mk= cin.get();
if(mk=='n')break;
names.clear();
}
return 0;
}