file input-output and virtual functions

[greenmort]

Please, help with file output and input of objects. I have base class "firstbase", and its derivative "second". I try to output to file jbject of derivative class, and it seems to be OK. But after declaring functions of base class as virtual, file input is wrong. What am I doing wrong? Thank you.

 #include "stdafx.h"
#include <iostream>
#include <fstream>

using namespace std;

class basefirst
{
public:
	virtual ~basefirst(){};
	virtual void getdata();
	virtual void putdata();

protected:
	int a;
	double b;
	char cst[30];
};


void basefirst::getdata()
{
	cout << "input integer number "; cin >> a;
	cout << "input float number "; cin >> b;
	cout << "input string "; cin >> cst;
}

void basefirst::putdata()
{
	cout << "integer number " << a << endl;
	cout << "float number " << b << endl;
	cout << "string " << cst << endl;
}

class second : public basefirst
{
public:
	second(){}
	void getdata();
	void putdata();
private:
	float d;
};

void second::getdata()
{
	basefirst::getdata();
	cout << "input once more float number "; cin >> d;
}

void second::putdata()
{
	basefirst::putdata();
	cout << "once more float number " << d << endl;
}

int _tmain(int argc, _TCHAR* argv[])
{

	second *bf1;

	bf1 = new second;
	bf1->getdata();
	bf1->putdata();
	ofstream ofile;
	ofile.open("bfirst.txt", ios::binary);
	ofile.write(reinterpret_cast<char*>(bf1), sizeof(second));
	ofile.close();

	bf1 = new second;
	ifstream ifile;
	ifile.open("bfirst.txt", ios::binary);
	ifile.read(reinterpret_cast<char*>(bf1), sizeof(second));
	(*bf1).putdata();
	ifile.close();

	system("pause");
	return 0;
}

[E0p9LyTq]

What is the expected output and what are you actually getting?

You have a memory leak, using new on the same pointer twice without deleting it after the first use.