C++模板类的继承1 ：模板类继承模板类

       大学时代旧作。

      模板类的继承是C++中较为高级的一种用法，其语法与普通C++类的继承略有差别。本文实例演示了一个通过C++模板类继承实现排序算法的案例。代码如下：

1.   实现List基类

#ifndef LIST_H

#define LIST_H

#include <iostream>

using std::cout;

using std::endl;

 

enum Error_code { underflow, overflow, range_error, success, not_present,fail};

const int max_list = 100;

 

template <class List_entry>

class List

{

       // methods of List ADT

public:

 

       List();

       int size() const;

       bool full() const;

       bool empty() const;

       void clear();

       void traverse(void(*vist)(List_entry&));  // Traverse every elements in the List

       Error_code retrieve(int position, List_entry &x) const;

       Error_code replace(int position, const List_entry& x);

       Error_code  remove(int position, List_entry& x);

       Error_code  insert(int position, const List_entry &x);

 

protected:

 

       // The contiguous implementation is based on the array

       int count;

       List_entry entry[max_list];

};

// constructor

template<class List_entry>

List<List_entry>:: List()

{

       count = 0;

}

/***** 其余代码略***********/

#endif

2. 从模板类中派生一个模板子类

#ifndef SORTABLE_LIST

#define SORTABLE_LIST

 
#include "list.h"

 

template<class Record>

class Sortable_list : public List<Record>

{

   public:

          Sortable_list();

 

          // Insertion sorting

          void insertion_sort();

 

          // Selection sorting

          void selection_sort();

          int max_key(int low, int high);

          void swap(int low, int high);

 

          // Shell sorting

          void shell_sort();

          void sort_interval(int low, int increment);

 

       // Quick sorting

          void quick_sort();

          void recursive_quick_sort(int low, int high);

          int partition(int low, int high);

 

          // Heap sorting

          void heap_sort();

          void insert_heap(const Record& current, int low, int high);

          void build_heap();

 

};

// 派生类的构造函数，注意其语法差别

template<class Record>

Sortable_list<Record>::Sortable_list():List<Record>(){}

/********************其余代码略**************************************/

#endif

3. 测试代码

#include <iostream>

using std::cout;

using std::endl;

 

#include "list.h"

#include "Sortable_list.h"

 

void print(int &a)

{

       cout<<a<<" ";

}

int main()

{

    Sortable_list<int> myList;

       myList.insert(0,6);

       myList.insert(0,56);

       myList.insert(0,7);

       myList.insert(2,57);

       myList.insert(1,4);

       myList.insert(3,23);

       myList.insert(0,9);

       myList.insert(5,45);

       myList.insert(4,17);

       myList.insert(0,7);

       myList.insert(6,89);

       myList.insert(6,34);

       myList.insert(2,35);

  

       // Sortable list to test different soring methods

    Sortable_list<int> myList2 = myList;

       Sortable_list<int> myList3 = myList;

       Sortable_list<int> myList4 = myList;

       Sortable_list<int> myList5 = myList;

 

       // Print out the original list

       cout<<"All the entries in the original list: "<<endl;

       myList.traverse(print);

       cout<<endl;

 

    

    // Test the insert sorting

       cout<<"After the insert soring, we get:"<<endl;

       myList.insertion_sort();

       myList.traverse(print);

    cout<<endl;

 

    // Test the selection sorting

       cout<<"After the insert soring, we get:"<<endl;

       myList2.selection_sort();

       myList2.traverse(print);

    cout<<endl;

 

    // Test the shell sorting

    cout<<"After the  shell sort,we get :"<<endl;

    myList3.shell_sort();

     myList3.traverse(print);

       cout<<endl;

    

       // Test the quick sorting

    cout<<"After the  quick sort,we get :"<<endl;

    myList4.quick_sort();

     myList4.traverse(print);

       cout<<endl;

 

    

       // Test the heap sorting

    cout<<"After the  quick sort,we get :"<<endl;

    myList5.heap_sort();

     myList5.traverse(print);

       cout<<endl;

    return 0;

 

}