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C++ 中的代码重用

pairs.cpp

来源: C++ 中的代码重用

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原始代码预览

// pairs.cpp -- defining and using a Pair template
#include <iostream>
#include <string>
template <class T1, class T2>
class Pair
{
private:
    T1 a;
    T2 b;
public:
    T1 & first();
    T2 & second();
    T1 first() const { return a; }
    T2 second() const { return b; }
    Pair(const T1 & aval, const T2 & bval) : a(aval), b(bval) { }
    Pair() {}
};

template<class T1, class T2>
T1 & Pair<T1,T2>::first()
{
    return a;
}
template<class T1, class T2>
T2 & Pair<T1,T2>::second()
{
    return b;
}

int main()
{
    using std::cout;
    using std::endl;
    using std::string;
    Pair<string, int> ratings[4] =
    {
        Pair<string, int>("The Purpled Duck", 5),
        Pair<string, int>("Jaquie's Frisco Al Fresco", 4),
        Pair<string, int>("Cafe Souffle", 5),
        Pair<string, int>("Bertie's Eats", 3)
    };

    int joints = sizeof(ratings) / sizeof (Pair<string, int>);
    cout << "Rating:\t Eatery\n";
    for (int i = 0; i < joints; i++)
        cout << ratings[i].second() << ":\t "
             << ratings[i].first() << endl;
    cout << "Oops! Revised rating:\n";
    ratings[3].first() = "Bertie's Fab Eats";
    ratings[3].second() = 6;
    cout << ratings[3].second() << ":\t "
         << ratings[3].first() << endl;
   // std::cin.get();
   return 0; 
}
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