#include <iomanip.h>
#include <string.h>
#include <malloc.h>
#include <stdio.h>
//typedef int TElemType;
const int UINT_MAX=1000;
char str[50];
typedef struct
{
int weight;
int parent,lchild,rchild;
}HTNode,* HuffmanTree;
typedef char **HuffmanCode;
//-----------全局變量-----------------------
HuffmanTree HT;
HuffmanCode HC;
int w[50],i,j,n;
char z[50];
int flag=0;
int numb=0;
// -----------------求赫夫曼編碼-----------------------
struct cou{
char data;
int count;
}cou[50];
int min(HuffmanTree t,int i)
{ // 函數void select()調用
int j,flag;
int k=UINT_MAX; // 取k爲不小於可能的值,即k爲最大的權值1000
for(j=1;j<=i;j++)
if(t[j].weight<k&&t[j].parent==0)
k=t[j].weight,flag=j;
t[flag].parent=1;
return flag;
}
//--------------------slect函數----------------------
void select(HuffmanTree t,int i,int &s1,int &s2)
{ // s1爲最小的兩個值中序號小的那個
int j;
s1=min(t,i);
s2=min(t,i);
if(s1>s2)
{
j=s1;
s1=s2;
s2=j;
}
}
// --------------算法6.12--------------------------
void HuffmanCoding(HuffmanTree &HT,HuffmanCode &HC,int *w,int n)
{ // w存放n個字符的權值(均>0),構造赫夫曼樹HT,並求出n個字符的赫夫曼編碼HC
int m,i,s1,s2,start;
//unsigned c,f;
int c,f;
HuffmanTree p;
char *cd;
if(n<=1)
return;//檢測結點數是否可以構成樹
m=2*n-1;
HT=(HuffmanTree)malloc((m+1)*sizeof(HTNode)); // 0號單元未用
for(p=HT+1,i=1;i<=n;++i,++p,++w)
{
p->weight=*w;
p->parent=0;
p->lchild=0;
p->rchild=0;
}
for(;i<=m;++i,++p)
p->parent=0;
for(i=n+1;i<=m;++i) // 建赫夫曼樹
{ // 在HT[1~i-1]中選擇parent爲0且weight最小的兩個結點,其序號分別爲s1和s2
select(HT,i-1,s1,s2);
HT[s1].parent=HT[s2].parent=i;
HT[i].lchild=s1;
HT[i].rchild=s2;
HT[i].weight=HT[s1].weight+HT[s2].weight;
}
// 從葉子到根逆向求每個字符的赫夫曼編碼
HC=(HuffmanCode)malloc((n+1)*sizeof(char*));
// 分配n個字符編碼的頭指針向量([0]不用)
cd=(char*)malloc(n*sizeof(char)); // 分配求編碼的工作空間
cd[n-1]='\0'; // 編碼結束符
for(i=1;i<=n;i++)
{ // 逐個字符求赫夫曼編碼
start=n-1; // 編碼結束符位置
for(c=i,f=HT[i].parent;f!=0;c=f,f=HT[f].parent)
// 從葉子到根逆向求編碼
if(HT[f].lchild==c)
cd[--start]='0';
else
cd[--start]='1';
HC[i]=(char*)malloc((n-start)*sizeof(char));
// 爲第i個字符編碼分配空間
strcpy(HC[i],&cd[start]); // 從cd複製編碼(串)到HC
}
free(cd); // 釋放工作空間
}
//---------------------獲取報文並寫入文件---------------------------------
int InputCode()
{
//cout<<"請輸入你想要編碼的字符"<<endl;
FILE *tobetran;
if((tobetran=fopen("tobetran.txt","w"))==NULL)
{
cout<<"不能打開文件"<<endl;
return 0;
}
cout<<"請輸入你想要編碼的字符"<<endl;
gets(str);
fputs(str,tobetran);
cout<<"獲取報文成功"<<endl;
fclose(tobetran);
return strlen(str);
}
//--------------初始化赫夫曼鏈表---------------------------------
void Initialization()
{ int a,k,flag,len;
a=0;
len=InputCode();
for(i=0;i<len;i++)
{k=0;flag=1;
cou[i-a].data=str[i];
cou[i-a].count=1;
while(i>k)
{
if(str[i]==str[k])
{
a++;
flag=0;
}
k++;
if(flag==0)
break;
}
if(flag)
{
for(j=i+1;j<len;j++)
{if(str[i]==str[j])
++cou[i-a].count;}
}
}
n=len-a;
for(i=0;i<n;i++)
{ cout<<cou[i].data<<" "; //輸出統計結果
cout<<cou[i].count<<endl;
}
for(i=0;i<=n;i++)
{*(z+i)=cou[i].data;
*(w+i)=cou[i].count;
}
HuffmanCoding(HT,HC,w,n);
//------------------------打印編碼-------------------------------------------
cout<<"字符對應的編碼爲:"<<endl;
for(i=1;i<=n;i++)
{
puts(HC[i]);
}
//--------------------------將赫夫曼編碼寫入文件------------------------
cout<<"下面將赫夫曼編碼寫入文件"<<endl<<"...................."<<endl;
FILE *htmTree;
char r[]={' ','\0'};
if((htmTree=fopen("htmTree.txt","w"))==NULL)
{
cout<<"can not open file"<<endl;
return;
}
fputs(z,htmTree);
for(i=0;i<n+1;i++)
{
fprintf(htmTree,"%6d",*(w+i));
fputs(r,htmTree);
}
for(i=1;i<=n;i++)
{
fputs(HC[i],htmTree);
fputs(r,htmTree);
}
fclose(htmTree);
cout<<"已將字符與對應編碼寫入根目錄下文件htmTree.txt中"<<endl<<endl;
}
//---------------------編碼函數---------------------------------
void Encoding()
{
cout<<"下面對目錄下文件tobetran.txt中的字符進行編碼"<<endl;
FILE *tobetran,*codefile;
if((tobetran=fopen("tobetran.txt","rb"))==NULL)
{
cout<<"不能打開文件"<<endl;
}
if((codefile=fopen("codefile.txt","wb"))==NULL)
{
cout<<"不能打開文件"<<endl;
}
char *tran;
i=99;
tran=(char*)malloc(100*sizeof(char));
while(i==99)
{
if(fgets(tran,100,tobetran)==NULL)
{
cout<<"不能打開文件"<<endl;
break;
}
for(i=0;*(tran+i)!='\0';i++)
{
for(j=0;j<=n;j++)
{
if(*(z+j-1)==*(tran+i))
{
fputs(HC[j],codefile);
if(j>n)
{
cout<<"字符錯誤，無法編碼!"<<endl;
break;
}
}
}
}
}
cout<<"編碼工作完成"<<endl<<"編碼寫入目錄下的codefile.txt中"<<endl<<endl;
fclose(tobetran);
fclose(codefile);
free(tran);
}
//-----------------譯碼函數---------------------------------
void Decoding()
{
cout<<"下面對根目錄下文件codefile.txt中的字符進行譯碼"<<endl;
FILE *codef,*txtfile;
if((txtfile=fopen("txtfile.txt","w"))==NULL)
{
cout<<"不能打開文件"<<endl;
}
if ((codef=fopen("codefile.txt","r"))==NULL)
{
cout<<"不能打開文件"<<endl;
}
char *work,*work2,i2;
int i4=0,i,i3;
unsigned long length=10000;
work=(char*)malloc(length*sizeof(char));
fgets(work,length,codef);
work2=(char*)malloc(length*sizeof(char));
i3=2*n-1;
for(i=0;*(work+i-1)!='\0';i++)
{
i2=*(work+i);
if(HT[i3].lchild==0)
{
*(work2+i4)=*(z+i3-1);
i4++;
i3=2*n-1;
i--;
}
else if(i2=='0') i3=HT[i3].lchild;
else if(i2=='1') i3=HT[i3].rchild;
}
*(work2+i4)='\0';
fputs(work2,txtfile);
cout<<"譯碼完成"<<endl<<"內容寫入根目錄下的文件txtfile.txt中"<<endl<<endl;
free(work);
free(work2);
fclose(txtfile);
fclose(codef);
}
//-----------------------打印編碼的函數----------------------
void Code_printing()
{
cout<<"下面打印根目錄下文件CodePrin.txt中編碼字符"<<endl;
FILE * CodePrin,* codefile;
if((CodePrin=fopen("CodePrin.txt","w"))==NULL)
{
cout<<"不能打開文件"<<endl;
return;
}
if((codefile=fopen("codefile.txt","r"))==NULL)
{
cout<<"不能打開文件"<<endl;
return;
}
char *work3;
work3=(char*)malloc(51*sizeof(char));
do
{
if(fgets(work3,51,codefile)==NULL)
{
cout<<"不能讀取文件"<<endl;
break;
}
fputs(work3,CodePrin);
puts(work3);
}while(strlen(work3)==50);
free(work3);
cout<<"打印工作結束"<<endl<<endl;
fclose(CodePrin);
fclose(codefile);
}
//-------------------------------打印譯碼函數---------------------------------------------
void Code_printing1()
{
cout<<"下面打印根目錄下文件txtfile.txt中譯碼字符"<<endl;
FILE * CodePrin1,* txtfile;
if((CodePrin1=fopen("CodePrin1.txt","w"))==NULL)
{
cout<<"不能打開文件"<<endl;
return;
}
if((txtfile=fopen("txtfile.txt","r"))==NULL)
{
cout<<"不能打開文件"<<endl;
return;
}
char *work5;
work5=(char*)malloc(51*sizeof(char));
do
{
if(fgets(work5,51,txtfile)==NULL)
{
cout<<"不能讀取文件"<<endl;
break;
}
fputs(work5,CodePrin1);
puts(work5);
}while(strlen(work5)==50);
free(work5);
cout<<"打印工作結束"<<endl<<endl;
fclose(CodePrin1);
fclose(txtfile);
}
//------------------------打印赫夫曼樹的函數-----------------------
void coprint(HuffmanTree start,HuffmanTree HT)
{
if(start!=HT)
{
FILE * TreePrint;
if((TreePrint=fopen("TreePrint.txt","a"))==NULL)
{cout<<"創建文件失敗"<<endl;
return;
}
numb++;//該變量爲已被聲明爲全局變量
coprint(HT+start->rchild,HT);
cout<<setw(5*numb)<<start->weight<<endl;
fprintf(TreePrint,"%d\n",start->weight);
coprint(HT+start->lchild,HT);
numb--;
fclose(TreePrint);
}
}
void Tree_printing(HuffmanTree HT,int w)
{
HuffmanTree p;
p=HT+w;
cout<<"下面打印赫夫曼樹"<<endl;
coprint(p,HT);
cout<<"打印工作結束"<<endl;
}
//------------------------主函數------------------------------------
void main()
{
char choice;
while(choice!='q')
{ cout<<"\n******************************"<<endl;
cout<<" 歡迎使用赫夫曼編碼解碼系統"<<endl;
cout<<"******************************"<<endl;
cout<<"(1)要初始化赫夫曼鏈表請輸入'i'"<<endl;
cout<<"(2)要編碼請輸入'e'"<<endl;
cout<<"(3)要譯碼請輸入'd'"<<endl;
cout<<"(4)要打印編碼請輸入'p'"<<endl;
cout<<"(5)要打印赫夫曼樹請輸入't'"<<endl;
cout<<"(6)要打印譯碼請輸入'y'"<<endl;
if(flag==0)cout<<"\n請先初始化赫夫曼鏈表,輸入'i'"<<endl;
cin>>choice;
switch(choice)
{
case 'i':
Initialization();
break;
case 'e':
Encoding();
break;
case 'd':
Decoding();
break;
case 'p':
Code_printing();
break;
case 't':
Tree_printing(HT,2*n-1);
break;
case 'y':
Code_printing1();
break;
default:
cout<<"input error"<<endl;
}
}
free(z);
free(w);
free(HT);
}