#include <iostream>
#include <cstdlib>
using namespace std;

template <typename T>
class Array
{
private:
    T* ptrT;
    int size;
public:
    Array():  ptrT(0), size(0) {}
    Array(int);
    T& operator[](int);
};

template <typename T>
Array<T>::Array(int n) : ptrT(new T[n]), size(n)
{
    for (int i = 0; i < size; i++) ptrT[i] = 0;
}

template <typename T>
T& Array<T>::operator[](int index)
{
    if (index < 0 || index >= size)
    {
        cerr << "invalid Array index\n";
        return *ptrT;
    }
    else return ptrT[index];
}

class Fraction
{
private:
    int numer, denom;
public:
    Fraction(int z = 0) : numer(z), denom(0) {}
    Fraction(int n, int d) : numer(n), denom(d) {}
    friend ostream& operator<<(ostream&, const Fraction&);
};

ostream& operator<<(ostream& s, const Fraction& f)
{
    return s << f.numer << '/' << f.denom;
}

int main(void)
{
    int i;
    Array<int> a1(3);
    for (i = 0; i < 3; i++) a1[i] = (2 * i);
    for (i = 0; i < 3; i++) cout << a1[i] << endl;

    Array<float> a2(3);
    for (i = 0; i < 3; i++) a2[i] = (2.7 * i);
    for (i = 0; i < 3; i++) cout << a2[i] << endl;

    Array<char> a3(6);
    for (i = 0; i < 3; i++) a3[i] = 65+3*i;
    for (i = 0; i < 3; i++) cout << a3[i] << endl;

    Array<Fraction> a4(3);
    a4[0] = Fraction(3,4);
    a4[1] = Fraction(1,2);
    a4[2] = Fraction(5,8);
    for (i = 0; i < 3; i++) cout << a4[i] << endl;
}