c++ template 应用例子

tempale　函数，template class　的例子

#include <iostream>
#include <vector>

using namespace std;

template <typename T>
T compare_fn(T a, T b)
{
    return (a > b ? a : b);
}

template <typename T>
void print_vector(const vector<T> & tVec)
{
    cout << "it's vector:" << endl;
    for (typename vector<T>::const_iterator it=tVec.begin(); it!=tVec.end(); ++it)
    {
        cout << *it << " ";
    }

    cout << endl;
}

template <typename T>
class TCompare {
public:
    TCompare(const T a, const T b);

    T maxValue();
    T minValue();
private:
    T m_tValue1;
    T m_tValue2;
};

template <typename T>
TCompare<T>::TCompare(const T a, const T b)
: m_tValue1(a), m_tValue2(b)
{

}

template <typename T>
T TCompare<T>::maxValue()
{
    return (m_tValue1 > m_tValue2 ? m_tValue1 : m_tValue2);
}

template <typename T>
T TCompare<T>::minValue()
{
    return (m_tValue1 < m_tValue2 ? m_tValue1: m_tValue2);
}

#define ARRAY_SIZE(x) (sizeof(x)/sizeof(x[0]))

int main()
{
    cout << compare_fn(4, 5) << endl;
    cout << compare_fn(6, 3) << endl;
    cout << compare_fn(3.3, 4.5) << endl;
    cout << compare_fn('a', 'd') << endl;

    TCompare<int> a(4, 5);
    TCompare<int> b(6, 3);
    TCompare<float> c(3.3, 4.5);
    TCompare<char> d('a', 'd');

    cout << "max:" << a.maxValue() << endl;
    cout << "min:" << a.minValue() << endl;

    cout << "max:" << b.maxValue() << endl;
    cout << "min:" << b.minValue() << endl;

    cout << "max:" << c.maxValue() << endl;
    cout << "min:" << c.minValue() << endl;

    cout << "max:" << d.maxValue() << endl;
    cout << "min:" << d.minValue() << endl;

    int array_int[] = {1, 2, 3, 4, 5};
    char array_c[] = {'a', 'b', 'c'};

    vector<int> ivec(array_int, array_int + ARRAY_SIZE(array_int));
    print_vector(ivec);

    vector<char> cVec(array_c, array_c + ARRAY_SIZE(array_c));
    print_vector(cVec);

    return 0;
}