#include <fstream>
#include <iostream>
#include <string>
using namespace std;

template <class T>
class IO
{
private:
    fstream file;
    int eof()
    {
        return file.eof();
    }
public:
    IO(const string& filename = "temp.bin")
    {
        file.open(filename,ios_base::in | ios_base::out | ios_base::trunc | ios_base::binary);
    }
    void rewind()
    {
        file.seekg(0L);
        file.seekp(0L);
        file.clear();
    }
    IO& operator>>(T& t);
    IO& operator<<(const T& t);
    operator bool()
    {
        if (!file) return false;
        else return true;
    }
};

template <class T>
IO<T>& IO<T>::operator<<(const T& t)
{
    file.write((char*) &t,sizeof(T));
    return *this;
}

template <class T>
IO<T>& IO<T>::operator>>(T& t)
{
    file.read((char*)&t,sizeof(T));
    return *this;
}

class A
{
    int a;
public:
    friend istream& operator>>(istream& in, A& AA);
    friend ostream& operator<<(ostream& out, A& AA);
};

istream& operator>>(istream& in, A& AA)
{
    cout << "Enter an int for an A object => ";
    return in >> AA.a;
}

ostream& operator<<(ostream& out, A& AA)
{
    return out << AA.a;
}

class B
{
protected:
    double bl;
    char b2[16] ;
    long b3;
public:
    friend istream& operator>>(istream& in, B& BB);
    friend ostream& operator<<(ostream& out, B& BB);
};

istream& operator>>(istream& in, B& BB)
{
    cout << "Enter double, char* and long for a B object => ";
    return in >> BB.bl >> BB.b2 >> BB.b3;
}

ostream& operator<<(ostream& out, B& BB)
{
    return out << BB.bl << ' ' << BB.b2 << ' ' << BB.b3;
}

int main(void)
{
    A apple;
    IO<A> appleIO("apple.bin");
    cin >> apple;
    appleIO << apple;
    cin >> apple;
    appleIO << apple;

    B banana;
    IO<B> bananaIO("banana.bin");
    cin >> banana;
    bananaIO << banana;
    cin >> banana;
    bananaIO << banana;
    cin >> banana;
    bananaIO << banana;

    int temp;
    IO<int> intIO;
    intIO << rand() % 100;
    intIO << rand() % 100;
    intIO << rand() % 100;
    intIO << rand() % 100;
    intIO << rand() % 100;

    appleIO.rewind();
    while (appleIO >> apple) cout << apple << endl;
    bananaIO.rewind();
    while (bananaIO >> banana) cout << banana << endl;
    intIO.rewind();
    while (intIO >> temp) cout << temp << endl;
}