为什么编码输出不正确啊？
#include<iostream>
#include<cstring>
#include<cstdlib>
using namespace std;



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)
{    int i,m,S1,S2;int small1,small2;
     small1=small2=32767;  S1=S2=0;
HTNode *p=0;
if(n<=1)  return;
m=2*n-1;
HT=(HuffmanTree)malloc((m+1)*sizeof(HTNode));

for( p=HT+1,i=1; i<=n; ++i,++p,++w)
{ (*p).weight=*w;
   (*p).parent=0;
   (*p).rchild=0;
   (*p).rchild=0;
}
for(;i<=m;++i,++p)
{
(*p).lchild=0;
(*p).parent=0;
(*p).rchild=0;
(*p).weight=0;
}

for(i=n+1;i<=m;++i)

{ 
{ for (int j=1;j<=i-1;++j)
        if(HT[j].parent==0)
{  if(HT[j].weight<small1)
  {
   small2=small1;  S2=S1;
   small1=HT[j].weight;
  
   S1=j;
   }
   else if(HT[j].weight<small2)
   {
                   small2=HT[j].weight;
   S2=j;
   }
}
}


   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 *));
  char *cd=(char *)malloc(n*sizeof(char));
cd[n-1]='\0';
for(i=1;i<=n;++i)
{
    int start=n-1;
  for(int 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));

     strcpy(HC[i],&cd[start]);





}

free(cd);

}


int main()
{
int A[]={1,2,4,9};

HuffmanTree HT;
Huffmancode HC;
Huffmancoding( HT, HC,A,4);


for(int i=1;i<=4;++i)
{ for(int j=0;HC[i][j]!='\0';++j)
  cout<<HC[i][j];
cout<<endl; }
//cout<<HC[i]<<endl;
 



return 0;

}

谢谢，已经解决！