程序代码：

/*Tree.h*/
#include<list>
#include<iostream>
using namespace std;
template<class T>
class Tree{
    T*NA;
    list<int>*HL;
    int root;
    int sizeN,sizeC;
    int maxN;
public:
    Tree(int n = 100):root(-1), sizeN(0), sizeC(0), maxN(n){
        NA = new T[n];
        HL = new list<int>[n];
    }
    ~Tree(){ delete[]NA; delete[]HL; }
    int Empty()const{ return size == 0; }
    int Full()const{ return size == maxN; }
    int SizeN()const{ return sizeN; }
    int SizeC()const{ return sizeC; }
    int FindNode(const T&node)const;
    bool FindNode(const T&node, int pos)const;
    bool InsertN(const T&node);
    bool InsertC(const T&parent, const T&child);
    void readTree(const char*filename);
    void writeTree(const char*filename);
    friend ostream&operator<<(ostream ostr, const Tree<T>&t);
    friend istream&operator>>(istream istr, Tree<T>&t);
};

template<class T>
int Tree<T>::FindNode(const T&node)const{
    for (int i = 0; i < size; i++)
        if (NA[i] == node)
            return(i);
    return -1;
}

template<class T>
bool Tree<T>::FindNode(const T&node, int pos)const{
    if (pos < 0 || pos >= sizeN)
        return 0;
    node = NA[pos];
    return 1;
}

template<class T>
bool Tree<T>::InsertN(const T&node){
    if (sizeN == maxN)
        return 0;
    NA[sizeN] == node;
    sizeN++;
    return 1;
}
template<class T>
bool Tree<T>::InsertC(const T&parent, const T&child){
    int pi = FindNode(parent), cj = FindNode(child);
    if (pi == -1 || cj == -1 || pi == cj)
        return 0;
    HL[pi].insert(HL[pi].end(), cj);
    sizeC++;
    return 1;
}
template<class T>
istream &operator>>(istream &istr, Tree<T>&t){
    char str[50];
    int n;
    T parent, child;
    istr >> str >> n;
    istr >> str >> parent;
    t.InsertN(parent);
    t.root = t.sizeN - 1;
    istr << str;
    for (int i = 1; i <= n - 1; ++i){
        istr >> child;
        t.InsertN(child);
    }
    istr >> str >> n;
    for (int i = 1; i <= n; ++i){
        istr >> parent >> child;
        t.InsertC(parent, child);
    }
    return istr;
}

template<class T>
ostream &operator<<(ostream&ostr, const Tree<T>&t){
    for (int i = 0; i < t.sizeN; i++){
        ostr << i << '-' << t.NA[i] << ':';
        List<int>::iterator first = t.HL[i].begin(), last = t.HL[i].end();
        for (; fiist != last; ++first)
            ostr << '(' << *first << ')' << ' ';
        ostr << endl;
    }
    return (ostr);
}

程序代码：

/*main*/
#include<iostream>
#include<fstream>
#include<string>
#include"Tree.h"
using namespace std;
int main(){
    Tree<char>T(20);
    ifstream fin;
    fin.open("E:\\计算机语言\\c++\\c++程序\\课本例题\\Tree类\\Tree类\\treein.txt", ios::in || ios::_Nocreate);
    if (!fin){
        cout << "can not open E:\\treein.txt.\n";
        exit(1);
    }
    fin>>T;
    ofstream fout;
    fout.open("E:\\计算机语言\\c++\\c++程序\\课本例题\\Tree类\\Tree类\\treeout.txt", ios::out);
    if (!fout){
        cout << "cannot open E:\\treeout.txt.\n";
        exit(1);
    }
    fout << T;
    return 0;
}