算法源码之哈弗曼编码

本文没有论述哈弗曼编码的原理、过程。只是将其实现过程现于纸上，为更多朋友在紧急的时候提供方便。忘广大朋友提出批评与指正，后续将不断撰写常用的算法源码

#include<stdio.h>#include<stdlib.h>#define MAXVALUE  10typedef struct HTNode{ float weight;  //结点权重 int parent;   //当前结点的父节点 int LChild;  //当前结点的左子节点 int RChild; //当前结点的右子节点}HTNode;void select(HTNode hTree[],int n,int *s1,int *s2){//选择较小的两个结点，这里将s1和s2的地址传递过去  int i,j;  float min1,min2;  min1=min2=MAXVALUE;//要找两个较小的数   for(i=0;i<n;i++){  //在树中找最小结点   if(min1>hTree[i].weight&&hTree[i].parent==-1){//注意判断条件，hTree[i].parent==-1表示该节点还未被选过    *s1=i;   }  }  for(j=0;j<n;j++){  //在树中找次最小结点   if(min2>hTree[j].weight&&hTree[j].parent==-1&&(*s1)!=j){    *s2=j;   }  }}void crtHuffmanTree(HTNode hTree[],float p[],int r){//创建哈弗曼树   int i,s1,s2,m; m=2*r-1;//有r个叶子结点,当整棵树构建完毕时,结点总数为m个  for(i=0;i<r;i++){     //哈弗曼树的初态  hTree[i].weight=p[i];  hTree[i].LChild=-1;  hTree[i].parent=-1;  hTree[i].RChild=-1; }  for(i=r;i<m;i++){    select(hTree,i-1,&s1,&s2);//在树中找两个权值最小的,将下标值赋给s1,s2;    hTree[i].weight=hTree[s1].weight+hTree[s2].weight; hTree[s1].parent=i; hTree[s2].parent=i; hTree[i].LChild=s1; hTree[i].RChild=s2; hTree[i].parent=-1; } for(i=0;i<m;i++){  printf("%lf \n",hTree[i].weight); } printf("创建哈弗曼树完毕\n");}void main(){ HTNode hTree[2*4-1] ;//测试，假设有4个节点 float p[4]={2.00/5.00,1.00/5.00,1.00/5.00,1.00/5.00};//分别是这四个结点的权重 crtHuffmanTree(hTree,p,4);}