huffman压缩文件

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#include <iostream>
#include <math.h>
#include <map>
#include <queue>
#include <stdlib.h>
#include <fstream>
#include <string.h>
using namespace std;

typedef struct node{
	char ch;
	int val;
	char num;
	struct node *self,*left,*right;
	friend bool operator < (const node &a,const node &b)
	{
		return a.val > b.val;
	}
}node;

priority_queue<node> p;
char res[30];
char code[10000];
string s[256];		//哈夫曼编码 
string str;			//文件编码01集合 
string myCode;		//压缩过后编码 
void dfs(node *root,int level)  //对huffman树编码 
{
	if(root->left == root->right)
	{
		if(level == 0)
		{
			res[0] = '0';
			level++;
		}
		res[level] = '\0';
		printf("%c => %s\n",root->ch,res);
		for(int i = 0;res[i]!='\0';i++)
		{
			s[(int)root->ch] += res[i];
		}
	}
	else
	{
		res[level] = '0';
		dfs(root->left,level+1);
		res[level] = '1';
		dfs(root->right,level+1);
	}
}

void huffman(int *hash)   //生成huffman树 
{
	node *root,fir,sec;
	for(int i = 0 ; i < 256; i++)
	{
		if(!hash[i])
			continue;
		root=(node *)malloc(sizeof(node));
		root->self = root;
		root->left = root->right = NULL;
		root->ch = i;
		root->val = hash[i];
		p.push(*root);
		
	}
	while(p.size()>1)
	{
		fir = p.top();
		p.pop();
		sec = p.top();
		p.pop();
		root = (node *)malloc(sizeof(node));
		root->self = root;
		root->left = fir.self;
		root->right = sec.self;
		root->left->num = '0';
		root->right->num = '1';
		root->val = fir.val+sec.val;
		p.push(*root);
	}
	fir=p.top();
	p.pop();
	dfs(fir.self,0);
}

int read_file()  //读取文件 
{
	int length=0;
	ifstream inf("12345.txt");
	while(!inf.eof())
	{
		inf >> code[length++];
	}
	inf.close();
	return length;
}

void write_file()
{
	for(int i=0;code[i]!='\0';i++)
	{
		str += s[(int)code[i]];
	}
	cout << str << endl;
	int sum = 0;
	for(int i = 0,j = 0; i < str.length(); i++,j++,j = j % 7)
	{
		sum += pow((str[i]-'0')*2,6-j);
		if(j==6)
		{
			myCode += (char)sum;
			cout << sum << endl;
			sum = 0;
		}
	}
	ofstream open("myCode");
	open << myCode;
	open.close();
}

int main()
{
	read_file();
	int hash[256];
	memset(hash,0,sizeof(hash));
	for(int i=0;code[i]!='\0';i++)
	{
		hash[(int)code[i]]++;
	}
	node* huffm = huffman(hash);
	write_file();
	
	return 0;
}