huffman coding

#include<cstdio>
#include<cstdlib>
#include<cstring>
using namespace std;
int frequency[200];
struct node
{
    char c;
    int fre;
    node *lf,*rf;
};

node *store[1000],*now,*n1,*n2;
char codes[200][50];
void encode(node *head,char code[])
{
	if(head->c!='0')
	{
		printf("%c %s\n",head->c,code);
		strcpy(codes[head->c],code);
		return;
	}
	char cl[50];
	strcpy(cl,code);
	strcat(cl,"0");
	encode(head->lf,cl);
	char cr[50];
	strcpy(cr,code);
	strcat(cr,"1");
	encode(head->rf,cr);
}
int main()
{
    freopen("source.txt", "r", stdin);
	freopen("charcode.txt", "w", stdout);
    char c;
    int count=0,total=0,i;
    while(scanf("%c",&c)==1)
    {
        frequency[c]++;
        total++;
    }

    for(i='a';i<='z';i++)
    {
        now=(node*)malloc(sizeof(node));
        now->fre=frequency[i];
        now->c=i;
        store[count++] = now;
    }
    now=(node*)malloc(sizeof(node));
    now->fre=frequency[' '];
    now->c=' ';
    store[count++] = now;
    int elements=count-1;
    int min,minode;
	while(elements--)
	{
		min=10000000,minode=-1;
		for(i=0;i<count;i++)
		{
			if(store[i]!=NULL&&store[i]->fre<min)
			{
				min=store[i]->fre;
				minode=i;
			}
		}
		n1=store[minode];
		store[minode]=NULL;
		min=10000000,minode=-1;
		for(i=0;i<count;i++)
		{
			if(store[i]!=NULL&&store[i]->fre<min)
			{
				min=store[i]->fre;
				minode=i;
			}
		}
		n2=store[minode];
		store[minode]=NULL;
		now=(node*)malloc(sizeof(node));
		now->fre=n1->fre+n2->fre;
		now->c='0';
		now->lf=n1;
		now->rf=n2;
		store[count++]=now;
	}
	node *tree=store[count-1];
	char str[]="";
	encode(tree,str);
	freopen("source.txt", "r", stdin);
	freopen("output.txt", "w", stdout);
	 while(scanf("%c",&c)==1)
    {
        printf("%s",codes[c]);
    }
	//while(1);
    return 0;
}