数据结构---哈夫曼编码

#include<iostream>#include<string>using namespace std;#define max 100#define INF 33333333333typedef struct{string data;  //结点值double weight;//权重int parent,lchild,rchild;}HTnode;HTnode ht[max];typedef struct{char cd[max];//存放当前结点的哈夫曼编码int start;//存放该结点哈夫曼编码的起始位置}HCode;HCode hcd[max];/**n：n个叶子结点,共有2n-1个结点*/void createHTnode(HTnode ht[],int n)//构造哈夫曼树{int i,k,lnode,rnode;double min1,min2;for(i=0;i<2*n-1;i++)ht[i].parent=ht[i].lchild=ht[i].rchild=-1;for(i=n;i<=2*n-2;i++){min1=min2=INF;lnode=rnode=-1;for(k=0;k<=i-1;k++)//在ht[0...i-1]中找权值最小的两个结点{if(ht[k].parent==-1){if(ht[k].weight<min1){min2=min1;rnode=lnode;min1=ht[k].weight;lnode=k;}else if(ht[k].weight<min2){min2=ht[k].weight;rnode=k;}}}ht[i].weight=ht[lnode].weight+ht[rnode].weight;ht[i].lchild=lnode;ht[i].rchild=rnode;ht[lnode].parent=i;ht[rnode].parent=i;}}void createHCode(HTnode ht[],HCode hcd[],int n0)//根据哈夫曼树求对应的哈夫曼编码{int i,f,c;HCode hc;for(i=0;i<n0;i++){hc.start=n0;c=i;f=ht[i].parent;while(f!=-1){if(ht[f].lchild==c)hc.cd[hc.start--]='0';elsehc.cd[hc.start--]='1';c=f;f=ht[f].parent;}hc.start++;//start指向哈夫曼编码的最开始的字符hcd[i]=hc;}}void display(HTnode ht[],HCode hcd[],int n){int i,k;int sum=0,m=0,cnt;cout<<"哈夫曼编码为："<<endl;for(i=0;i<n;i++){cnt=0;cout<<ht[i].data<<"\t"<<":";          for (k=hcd[i].start; k<=n; k++)          {              cout<<hcd[i].cd[k];              cnt++;          }          m+=ht[i].weight;          sum+=(ht[i].weight*cnt);          cout<<endl;      }      cout<<"平均长度="<<(float)sum/m<<endl;}int main(){int n=15;      string str[]= {"The","of","a","to","and","in","that","he","is","at","on","for","His","are","be"};      int f[]= {1192,677,541,518,462,450,242,195,190,181,174,157,138,124,123};      for (int i=0; i<n; i++)      {          ht[i].data=str[i];          ht[i].weight=f[i];      }      createHTnode(ht,n);      createHCode(ht,hcd,n);      display(ht,hcd,n);      return 0;  return 0;}