数据结构实验4---用HuffmanTree进行编码、译码

#include<iostream>#include<stdio.h>#include<fstream>#include<string>#include<string.h>#include<stdlib.h>#include<math.h>#define Status int #define OK 1 #define ERROR 0#define STACK_INIT_SIZE 10#define MAX_LINE 10#define MAX_CHAR 200using namespace std;typedef struct{ int weight, parent, lchild, rchild; char data;}ElemType;typedef struct{ ElemType * elem; int length; int listsize;}Sqlist;typedef char * * HuffmanCode;typedef struct{ char *base; char *top; int stacksize;}SqStack;Status InitStack(SqStack &s){//初始化栈函数。 s.base = (char *)malloc(STACK_INIT_SIZE * sizeof(char)); if(!s.base)  exit(OVERFLOW); s.top = s.base; s.stacksize = STACK_INIT_SIZE; return OK;}Status push(SqStack &s, char e){//入栈函数。 if(s.top - s.base >= s.stacksize){  s.base = (char *)realloc(s.base,   (s.stacksize + STACK_INIT_SIZE) * sizeof(char));  if(!s.base)   exit(OVERFLOW);  s.top = s.base + s.stacksize;  s.stacksize += STACK_INIT_SIZE; } *s.top++ = e; return OK;}Status pop(SqStack &s, char &e){//出栈函数。 if(s.top == s.base)  return ERROR; e = * --s.top; return OK;}Status emptystack(SqStack s){//判定栈空的函数。 if(s.base == s.top)  return OK; else  return ERROR;}void select(Sqlist HT, int i, int &s1, int &s2, static bool *flag){ //选择两个未被访问的最大的数组下标分别赋给s1, s2。 int n = (HT.listsize + 1)/2; int weight, xiabiao; //求第一个最大值。 for(int i = 0; i < HT.listsize; i++){  if(flag[i] != true){   weight = HT.elem[i].weight;   xiabiao = i;   break;  } } for(int j = 1; j < i; j++){  if(HT.elem[j].weight < weight && flag[j] == false){   weight = HT.elem[j].weight;   xiabiao = j;  } } s1 = xiabiao; flag[s1] = true; //求第二个最大值。 for(int i = 0; i < HT.listsize; i++){  if(flag[i] != true){   weight = HT.elem[i].weight;   xiabiao = i;   break;  } } for(int j = 1; j < i; j++){  if(HT.elem[j].weight < weight && flag[j] == false){   weight = HT.elem[j].weight;   xiabiao = j;  } } s2 = xiabiao; flag[s2] = true;}void CreateHuffmanTree(int n, int *w, Sqlist &HT, char *ch){ int m = 2 * n - 1; HT.elem = new ElemType[m]; HT.length = HT.listsize = m; for(int i = 0; i < n; i++){  HT.elem[i].weight = w[i];  HT.elem[i].parent = -1;   HT.elem[i].lchild = -1;  HT.elem[i].rchild = -1;  HT.elem[i].data = ch[i]; } static bool *flag; flag = new bool[HT.listsize]; for(int i = 0; i < HT.listsize; i++){  flag[i] = false; } for(int i = n; i < m; i++){  int s1, s2;  select(HT, i, s1, s2, flag);  HT.elem[i].weight = HT.elem[s1].weight + HT.elem[s2].weight;  HT.elem[i].parent = -1;  HT.elem[i].lchild = s1;  HT.elem[i].rchild = s2;  HT.elem[s1].parent = i;  HT.elem[s2].parent = i; } delete []flag;}Status HuffmanCoding(Sqlist HT, HuffmanCode &HC, int n){ SqStack s; InitStack(s); HC = new char* [n]; for(int i = 0; i < n; i++){  int j = i;  while(HT.elem[j].parent != -1){   int parent = HT.elem[j].parent;   if(HT.elem[parent].lchild == j){    push(s, '0');   }else{    push(s,'1');   }   j = parent;  }  push(s, '\0');  HC[i] = new char[s.top - s.base];  strcpy(HC[i], s.base);  strrev(HC[i]);  s.top = s.base; } free(s.base); return OK;}void tongji(string filename, char *&ch, int *&w, int &n, char **&s, int &line){//文本内容只允许[a-z]和‘#’； //filename是打开文件名；ch是存放文本中出现的字符的数组； //w是存放对应的字符的weight的数组，n是出现的字符的个数 s = new char*[MAX_LINE]; ifstream in; in.open(filename, ios::in); string s1; static int count_Line = 0; for(int i = 0; getline(in, s1); i++){//要求文件行数小于10，每行字符数小于200  const char *s2;  s2 = s1.c_str();  s[i] = new char[MAX_CHAR];  strcpy(s[i], s2);  count_Line++; } line = count_Line; int *w1 = new int [27];//动态创建w1；加上一个'#‘； for(int i = 0; i < 27; i++){//把初始值设为0；  w1[i] = 0; } for(int i = 0; i < count_Line; i++){  for(int j = 0; s[i][j] != '\0'; j++){   int t1 = s[i][j] - 'a';//假设只有小写字母   w1[t1]++;  } } static int k = 0; ch = new char[28];//还包含一个’\0';//并且多预留一个空间存放'#'; int w2[27]; for(int i = 0; i < 27; i++){  if(w1[i]){   ch[k] = char('a' + i);   w2[k] = w1[i];   ++k;  } } w = new int[k + 1];//多预留一个空间存放‘#’的权值0； for(int i = 0; i < k; i++){  w[i] = w2[i]; } n = k + 1; w[k] = 0; ch[k] = '#'; ch[k + 1] = '\0'; in.close(); delete [] w1;}void bianma(char **s, HuffmanCode HC, char *ch, int line, int n){// ofstream out; out.open("temp.txt", ios::out);//这里先写死 for(int i = 0; i < line; i++){//只要小于行数，一直做;  char *s2 = new char[400];//0100101010000型的字符  s2[0] = '/';  for(int j = 0; s[i][j] != '\0'; j++){   for(int k = 0; k < n; k++){    if(ch[k] == s[i][j]){     if(s2[0] == '/'){      strcpy(s2, HC[k]);     }else{      //strcpy(s2, HC[k]);      strcat(s2, HC[k]);//这样写没有问题     }     //cout<<s2<<endl;//ceshi    }    }  }  //char *s3 = new char[s2.length() + 1];//动态创建s3；  //strcpy(s3, s2.c_str());//10000101010类型的字符  int n1;  static int count1 = 0;  int intofchar = 0;  char s4 = ' ';  int char_to_int(char *cstr1, static int &count1,int &intofchar, int n, HuffmanCode HC);  int flag;  // delete [] s3;//动态销毁s3；  cout<<"bianma "<<s2<<endl;//ceshi  while(flag = char_to_int(s2, count1, intofchar, n, HC)){//此处为赋值   s4 = (char)(intofchar);//可以转但是char只有0-127，而s4为0-255,所以把s4同样改成‘7’位，即0-127   out<<s4;//输出到文本  }  s4 = (char)(intofchar);//可以转但是char只有0-127，而s4为0-255,所以把s4同样改成‘7’位，即0-127  out<<s4;//输出到文本  out<<'\n';  count1 = 0;  delete [] s2; } out.close();}void bianli(Sqlist HT, char *s2, int n){ ofstream out; out.open("data2.txt", ios::app); int static m; m = 2 * n - 1 - 1; for(int i = 0; s2[i] != '\0'; i++){  if(s2[i] == '0' && HT.elem[m].lchild == -1){   if(HT.elem[m].data != '#'){    out<<HT.elem[m].data;    i = i - 1;    m = 2 * n - 1 - 1;   }else{    return;   }  }else if(s2[i] == '1' && HT.elem[m].rchild == -1){   if(HT.elem[m].data != '#'){    out<<HT.elem[m].data;    i = i - 1;    m = 2 * n - 1 - 1;   }else{    return;   }  }else if(s2[i] == '1'){   m = HT.elem[m].rchild;  }else{   m = HT.elem[m].lchild;  }  } out.close(); return;}void jiema(Sqlist HT, int n){//jieguo是解码之后的内容，可以在控制台打印,也可以存到文件中； ifstream in; string str1; in.open("temp.txt", ios::in); while(getline(in, str1)){  char* int_to_char(string str1);//函数声明  char *s2 = int_to_char(str1);  cout<<"jiema "<<s2<<endl;//测试  bianli( HT, s2, n);  ofstream out;  out.open("data2.txt", ios::app);  out<<'\n';  out.close();  delete [] s2; } in.close();}int char_to_int(char *cstr1, static int &count1, int &intofchar, int n, HuffmanCode HC){ int x; intofchar = 0; for(x = count1; cstr1[x] != '\0'&& x - count1 < 7; x++){  if(cstr1[x] == '1'){   intofchar = intofchar + (int)(pow(double(2), (7 - (x - count1) - 1)));  }  } if(x - count1 != 7){  for(int z = 0; z < 7 - (x - count1); z++){   if(HC[n - 1][z] == 1){    intofchar = intofchar + (int)(pow(double(2), (7 - (x - count1) - z)));   }  }  return 0; }else{   count1 = count1 + 7;  return 1; }}char* int_to_char(string str1){//ok char *s1 = new char[str1.length() + 1]; strcpy(s1, str1.c_str()); char *s2 = new char[700];//存放0101010001011100100010010001010型的字符串； int t1 = char(s1[0]);//第一次的时候用strcpy char s3[8]; int i = 0; for( ; t1 / 2 != 0; i++){  if(t1 % 2 == 0){   s3[i] = '0';  }else{   s3[i] = '1';  }  t1 = t1 / 2; } s3[i] = '1'; if(i != 7){  while(i < 6){   s3[i] = '0';   i++;  } } s3[7] = '\0'; strrev(s3); strcpy(s2,s3); for(int j = 1; s1[j] != '\0'; j++){//后面的用循环，用strcat  int t1 = char(s1[j]);  char s3[8];  i = 0;  for( ; t1 / 2 != 0; i++){   if(t1 % 2 == 0){    s3[i] = '0';   }else{    s3[i] = '1';   }   t1 = t1 / 2;  }  s3[i] = '1';  if(i != 7){   while(i < 6){    s3[i] = '0';    i++;   }  }  s3[7] = '\0';  strrev(s3);  strcat(s2,s3); } delete [] s1; return s2;}int main(){//主函数。 //-------------------测试HuffmanTree和HuffmanCode //int n; //Sqlist HT; //HuffmanCode HC; ////读文件。 //fstream in; //in.open("jiedian.txt", ios::in); //in>>n;//读入data的个数 //int *w = new int[n]; //char *ch = new char[n]; //for(int i = 0; i < n; i++){//读入datas // in>>ch[i]; //} //for(int i = 0; i < n; i++){//读入weights // in>>w[i]; //} ////关闭文件。 //CreateHuffmanTree(n, w, HT,ch); //HuffmanCoding(HT, HC, n); //for(int i = 0; i < n; i++){//ceshi // cout<<"code i = "<<i<<": "<<HC[i]<<endl; //} //in.close(); //delete [] w; //delete [] HT.elem; //delete [] *HC; //delete [] HC; //-----------------------------测试结束 //-----------------------------程序结果显示 char *ch = NULL; int *w = NULL; int n = 0; int line = 0; string filename = "data1.txt";//data1.txt是待编码的文本 char **s; tongji(filename, ch, w, n, s, line); HuffmanCode HC; Sqlist HT; CreateHuffmanTree(n, w, HT,ch); HuffmanCoding(HT, HC, n); //for(int i = 0; i < n + 1; i++){//ceshi // cout<<ch[i]<<" "<<HC[i]<<endl; //} bianma(s, HC, ch, line, n); jiema(HT, n); //-------------------------------程序结果显示}

 

哈夫曼树的结构示例：