/**************************************************
构造赫夫曼树
by Rowandjj
2014/6/2
**************************************************/
#include<IOSTREAM>
using namespace std;#define UINT_MAX 0xfffffffftypedef struct _BITREE_//二叉树
{int data;//存放节点的圈中struct _BITREE_ *lChild;struct _BITREE_ *rChild;
}Bitree,*pBitree;typedef struct _HUFFMANTREE_//赫夫曼树
{unsigned int weight;unsigned int parent;unsigned int lChild;unsigned int rChild;
}HuffmanTree,*pHuffmanTree;int iCount = 0;//叶子节点数
int iIndex = 1;//索引//-----------------------------------------void CreateBiTree(pBitree* pBitreeTemp);//创建二叉树
void CreatreArray(pHuffmanTree& pHuffmanTreeTemp,pBitree pBitreeTemp);//将二叉树每个节点的值作为权放进赫夫曼树中
pHuffmanTree InitHuffmanTree();//初始化赫夫曼树，
void CreateHuffmanTree(pHuffmanTree& pHuffmanTreeTemp);//创建赫夫曼树
int GetNode(pHuffmanTree& pHuffmanTreeTemp,int i);//获取赫夫曼树中位置0-i中值最小的节点的索引
void SelectNode(pHuffmanTree& pHuffmanTreeTemp,int i,int *m,int *n);//选择赫夫曼树数组中值最小的两个节点的索引（不包含已有父节点的节点）
void DestroyTree(pBitree* pBitreeTemp);
void DestroyHuffmanTree(pHuffmanTree& pHuffmanTreeTemp);
int main()
{int i;//创建二叉树pBitree pBitreeTemp;CreateBiTree(&pBitreeTemp);//初始化赫夫曼树pHuffmanTree pHuffmanTreeTemp = InitHuffmanTree();//初始化赫夫曼树的叶子节点的权CreatreArray(pHuffmanTreeTemp,pBitreeTemp);for(i = 1; i <= iCount ; i++){cout<<pHuffmanTreeTemp[i].weight<<" ";}cout<<endl;//创建赫夫曼树CreateHuffmanTree(pHuffmanTreeTemp);for(i = 1; i <= 2*iCount-1 ; i++){cout<<pHuffmanTreeTemp[i].weight<<" ";}cout<<endl;DestroyTree(&pBitreeTemp);DestroyHuffmanTree(pHuffmanTreeTemp);return 0;
}void CreateBiTree(pBitree* pBitreeTemp)
{int data;cin>>data;if(data == -1){return;}*pBitreeTemp = (pBitree)malloc(sizeof(Bitree));if(*pBitreeTemp == NULL){return;}(*pBitreeTemp)->data = data;(*pBitreeTemp)->lChild = NULL;(*pBitreeTemp)->rChild = NULL;CreateBiTree(&(*pBitreeTemp)->lChild);CreateBiTree(&(*pBitreeTemp)->rChild);iCount++;
}
pHuffmanTree InitHuffmanTree()
{int num = 2*iCount - 1;//赫夫曼树的节点总数为：叶子节点数*2-1pHuffmanTree pTemp = (pHuffmanTree)malloc(sizeof(HuffmanTree)*(num+1));//0位不存if(pTemp == NULL){return NULL;}for(int i = 0; i <= num; i++){pTemp[i].lChild = 0;pTemp[i].rChild = 0;pTemp[i].parent = 0;pTemp[i].weight = 0;}return pTemp;
}
void CreatreArray(pHuffmanTree& pHuffmanTreeTemp,pBitree pBitreeTemp)
{if(pBitreeTemp == NULL || pHuffmanTreeTemp == NULL){return;}pHuffmanTreeTemp[iIndex].weight = pBitreeTemp->data;iIndex++;CreatreArray(pHuffmanTreeTemp,pBitreeTemp->lChild);CreatreArray(pHuffmanTreeTemp,pBitreeTemp->rChild);
}
int GetNode(pHuffmanTree& pHuffmanTreeTemp,int i)
{int min = UINT_MAX;int flag;for(int j = 1; j <= i; j++){if(pHuffmanTreeTemp[j].weight < min && pHuffmanTreeTemp[j].parent == 0)//已有父节点的不算{min = pHuffmanTreeTemp[j].weight;flag = j;}}pHuffmanTreeTemp[flag].parent = 1;//防止两次调用获取的索引相同return flag;
}
void SelectNode(pHuffmanTree& pHuffmanTreeTemp,int i,int *m,int *n)//m为序号小的那个
{*m = GetNode(pHuffmanTreeTemp,i);*n = GetNode(pHuffmanTreeTemp,i);int t;if(*m > *n){t = *m;*m = *n;*n = t;}
}void CreateHuffmanTree(pHuffmanTree& pHuffmanTreeTemp)
{if(pHuffmanTreeTemp == NULL){return;}int m = 0,n = 0;for(int i = iCount+1;i <= 2*iCount-1; i++){SelectNode(pHuffmanTreeTemp,i-1,&m,&n);pHuffmanTreeTemp[m].parent = pHuffmanTreeTemp[n].parent = i;//构造两个最小权重的节点的父节点pHuffmanTreeTemp[i].lChild = m;pHuffmanTreeTemp[i].rChild = n;pHuffmanTreeTemp[i].weight = pHuffmanTreeTemp[m].weight+pHuffmanTreeTemp[n].weight;}}void DestroyTree(pBitree* pBitreeTemp)
{if(*pBitreeTemp == NULL){return;}if((*pBitreeTemp)->lChild){DestroyTree(&(*pBitreeTemp)->lChild);}if((*pBitreeTemp)->rChild){DestroyTree(&(*pBitreeTemp)->rChild);}free(*pBitreeTemp);*pBitreeTemp = NULL;
}void DestroyHuffmanTree(pHuffmanTree& pHuffmanTreeTemp)
{if(pHuffmanTreeTemp){free(pHuffmanTreeTemp);}pHuffmanTreeTemp = NULL;
}

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