classtemplaterecursion.cpp

来自「C++ sample code, for the book: C++ blac」· C++ 代码 · 共 67 行

#include <iostream>
using namespace std;

template <class T, int number_of_elements>
class Array
{
    T *ptr_to_array;
public:
    explicit Array();
    Array(const Array & a);
    ~Array();
    T& operator= (const Array & a);
    T& operator[](int index) {return ptr_to_array[index];}
};

template <class T, int number_of_elements>
Array<T, number_of_elements>::Array()
{
    ptr_to_array = new T[number_of_elements];
}

template <class T, int number_of_elements>
Array<T, number_of_elements>::Array(const Array & a)
{
    number_of_elements = a.number_of_elements;
    T *ptr_to_array = new T[number_of_elements];

    for(int loop_index = 0; loop_index < number_of_elements; loop_index++) {
        ptr_to_array[loop_index] = a.ptr_to_array[loop_index];
    }   
}

template <class T, int number_of_elements>
T& Array<T, number_of_elements>::operator= (const Array & a)
{
    if(this == &a) return *this;
    delete[] ptr_to_array;

    number_of_elements = a.number_of_elements;
    T *ptr_to_array = new T[number_of_elements];

    for(int loop_index = 0; loop_index < number_of_elements; loop_index++) {
        ptr_to_array[loop_index] = a.ptr_to_array[loop_index];
    }   
    return *this;
}

template <class T, int number_of_elements>
Array<T, number_of_elements>::~Array()
{
    delete[] ptr_to_array;
}

int main()
{
    Array<Array<float, 3>, 10> scores;    

    scores[0][1] = 85;

    cout << "The student scored " << scores[0][1] << endl;

    return 0;
}