> 还有btree,insert,preorder,自己写吧
> void main()
> {
> 	string s[100];
> 	int total=0,current=0,nextlen,currentlen;
> 	cin>>s[total];
> 	while(s[total]!="$")
> 	{
> 		total++;
> 		cin>>s[total];
> 	}
> 
> 	while(current!=total)
> 	{
> 
> 		currentlen=current;
> 		while(s[currentlen]!="*"&&s[currentlen]!="$")
> 			currentlen++;//s currentlen=*
> 
> 		if(s[currentlen]=="$")
> 			nextlen=-1;
> 		else nextlen=currentlen+1;
> 		currentlen--;
> 		btree * root=new btree;
> 		root->food='@';
> 		while(currentlen!=current-1)
> 		{
> 
> 			int len;
> 			for(int i=0;s[currentlen][i]!='\0';i++);
> 				len=i;
> 			for(i=1;i<=len;i++){
> 				insert(root,s[currentlen][i-1]);
> 
> 			}
> 			currentlen--;
> 		}
> 		preorder(root);
> 
> 		current=nextlen;
> 
> 		cout<<endl;
> 		if(nextlen==-1)
> 			break;
> 	}
> }


thanks very much ~~