讲解请参考 赫夫曼

------ 赫夫曼树和赫夫曼编码的存储表示------

typedef struct {unsigned int weight;unsigned int parent,lchild,rchild;
}HTNode,*HuffmanTree;
typedef char ** HuffmanCode;void HuffmanCoding(HuffmanTree& HT,HuffmanCode & HC,int *w,int n)  {if (n < 1) return;\int m = 2* n + 1;HT = (HuffmanTree) malloc (m+1)* sizeof(HTNode); //0 号单元未用for ( HuffmanTree p = HT; i=1; i<=n; ++i; ++p; ++w)  *p = {*w,0,0,0,0};for(; i<=m; ++i; ++p)*p = {0,0,0,0};for(i = n+1; i<=m; i++) {  //建立HuffmanTreeSelect(HT,i-1,s1,s2);HT[s1].parent = i; HT[s2].parent = i; HT[i].lchild = s1;HT[i].rchild = s2;HT[i].weight = HT[s1].weight + HT[s2].weight;}HC = (HuffmanCode)malloc((n+1)* sizeof(char*));cd = (char*) malloc(n* sizeof(char));cd [n-1] = "\0";for ( i=1; i<=n; i++) {int start = n-1;for ( c=i, f = HT[i].parent; f!=0; c=f; f = HT[f].parent )if( HT[f].lchild == c )  cd [--start] = "0";else cd [--start] = "1";HC[i] = (char*) malloc ( (n-start)* sizeof(char)); strcyp(HC[i],&cd[start]);}free(cd);}

------ 无栈非递归遍历赫夫曼树，求赫夫曼编码------

HC = (HuffmanCode) malloc ( (n+1) *　sizeof(char*)); 
int p = m, cdlen = 0;for ( int i=1; i<=m; ++i)  HT[i].weight = 0;while(p) {if ( HT[p].weight == 0 ) {HT[p].weight = 1; if ( HT[p].lchild != 0) {p = HT[p].lchild; cd[cdlen++] = "0";}else if ( HT[p].lchild == 0) {HC[p] = (char*) malloc ((cdlen+1) * sizeof(char));cd[cdlen] = "\0"; strcpy(HC[p],cd);}}else if ( HP[p].weight == 1) {HT[p].weight = 2;if ( HT[p].rchild != 0) {p = HT[p].rchild;cd [cdlen++] = "1";}else {HT[p].weight = 0; p = HT[p].parent; --cdlen;}}    
}