Data structure routines--Huffman tree

This paper is the basic Data Structure series (6): Tree and two-fork tree in the 15th class Huffman tree routines.

#include <stdio.h>#include <string.h>#define N //leaf knot points #define M 2*n-1 //Total number of nodes in tree //Huffman tree node structure typetypedef struct{CharData//Node value    DoubleWeight//Weight    intParent//Parent node    intLchild;//Left child knot point    intRchild;//Right child knot point} Htnode;//Each node Huffman encoded structure typetypedef struct{CharCd[n];//Store Huffman code    intStart;} Hcode;//Construction Huffman TreevoidCreateht (Htnode ht[],intN) {intI,k,lnode,rnode;Doublemin1,min2; for(i=0; i<2*n-1; i++)//All nodes related domain set initial value -1ht[i].parent=ht[i].lchild=ht[i].rchild=-1; for(I=n; i<2*n-1; i++)//Construction Huffman Tree{min1=min2=32767;//lnode and Rnode for two node positions with minimum weightlnode=rnode=-1; for(k=0; k<=i-1; k++)if(ht[k].parent==-1)//Find only in nodes that have not yet constructed a two-fork tree{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; }}//Implement Huffman codingvoidCreatehcode (Htnode Ht[],hcode hcd[],intN) {intI,f,c; Hcode HC; for(i=0; i<n; i++)//According to Huffman tree to find Huffman code{hc.start=n;        C=i; F=ht[i].parent; while(f!=-1)//sequential until root node{if(HT[F].LCHILD==C)//Handle left child nodehc.cd[hc.start--]=' 0 ';Else                    //Handle Right child nodehc.cd[hc.start--]=' 1 ';            C=f;        F=ht[f].parent; } hc.start++;//start Point Huffman encoding the first characterHCD[I]=HC; }}//Output Huffman codevoidDisphcode (Htnode Ht[],hcode hcd[],intN) {intI,k;Doublesum=0, m=0;intJprintf("Output Huffman code: \ n");//Output Huffman code     for(i=0; i<n; i++) {j=0;printf("%c:\t", Ht[i].data); for(K=hcd[i].start; k<=n; k++) {printf("%c", Hcd[i].cd[k]);        j + +;        } m+=ht[i].weight; Sum+=ht[i].weight*j;printf("\ n"); }printf("\ n Average length =%g\n",1.0*sum/m);}intMain () {intn=8I//n Indicates the number of initial strings    Charstr[]= {' A ',' B ',' C ',' d ',' E ',' F ',' G ',' h '};Doublefnum[]= {0.07,0.19,0.02,0.06,0.32,0.03,0.21,0.1};    Htnode Ht[m]; Hcode Hcd[n]; for(i=0; i<n;        i++) {Ht[i].data=str[i];    Ht[i].weight=fnum[i]; }printf("\ n");    Createht (Ht,n);    Createhcode (Ht,hcd,n); Disphcode (Ht,hcd,n);printf("\ n");return 0;}

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Data structure routines--Huffman tree