构造n个给定值节点构成的森林；

选择权值最小的两个构成叶子节点，根节点权值为两叶子节点之和，

删除原有的两棵树，将这棵树加入森林中；

重复这两部直到只有一棵树为止，此树就是哈夫曼树；

#pragma once
#include<iostream>
namespace stlname 
{
	using std::cin;
	typedef struct
		{
		int weight;//权重
		int parent, lch, rch;	//父节点，孩子节点下标
		}HTNode,*HuffmanTree;
	void Seclect(HuffmanTree HT,int i ,int* s1,int* s2);
	
	void CreateHuffmanTree(HuffmanTree HT, int n)//初始化
		{
		if (n <= 1)return;
		int m = 2 * n - 1;
		HT = new HTNode[m+1]();//2n个节点；

			for (int i = 1; i < m + 1; i++)
			{
				HT[i].lch = HT[i].rch = HT[i].parent = 0;//初始化

			}
			for (int i = 1; i <= n; i++)std::cin >> HT[i].weight;

			int* s1, * s2 = NULL;
			for (int i = n + 1; i < m; i++)
				{
				Seclect(HT, i - 1, s1, s2);

				HT[*s1].parent = i; HT[*s2].parent = i;
				HT[i].lch = *s1; HT[i].rch = *s2;
				HT[i].weight = HT[*s1].weight + HT[*s2].weight;

				}

		}

	
		
			
}

 

 哈夫曼编码算法实现：

void CreateHuffmanCode(HuffmanTree HT, HuffmanCode  HC, int n)
	{
		HC = new char* [n + 1];
		char* cd = new char[n];
		cd[n - 1] = '\0';
		
		for (int i = 1; i < n; i++)
		{
			int start = n - 1; int c = i;
			int f = HT[i].parent;
			while (start != 0) {
				start--;
				if (HT[f].lch == c) { cd[start] == '0'; }
				else cd[start] = '1';
				c = f;
				f = HT[f].parent;
						
			}

			strcpy(HC[i],&cd[start]);
		}
		delete cd; cd = NULL;

	}