программа на Visua Studio

#include "stdafx.h"
 
#include <iostream>
#include <stdlib.h>
#include <stdio.h>
 
using namespace std;
 
FILE* fp;
char buf[200];
 
class Subject ;
Subject*  objects[100];
int numOfObjects;
 
class Subject
{
protected:
    char name[200];
public:
    virtual void print()=0;
    virtual void write(FILE* fp)=0;
};
 
class MathematicalSubject : public Subject
{
protected:
    unsigned int creationYear;
public:
    MathematicalSubject(char* n, unsigned int y)
    {
        strcpy(name, n);
        creationYear = y;
    }
    virtual void print()
    {
        cout << "MATHEMATICAL SUBJECT: name:" << name <<
            ", creationYear:" << creationYear
            << endl;
    }
    virtual void write(FILE* fp)
    {
        fprintf(fp, "%s %s %d\n", name, creationYear);
    }
};
 
class InformationSubject : public Subject
{
protected:
    unsigned int publishYear;
    float price;
public:
    InformationSubject(char* n, unsigned int y, float p)
    {
        strcpy(name, n);
        publishYear = y;
        price = p;
    }
    virtual void print()
    {
        cout << "INFORMATION SUBJECT: name:" << name <<
            ", publishYear:" << publishYear
            << ",price:" << price << endl;
    }
    virtual void write(FILE* fp)
    {
        fprintf(fp, "%s %s %d %5.2f\n",name, publishYear, price);
    }
};
 
void Output()
{
    for (int i = 0; i < numOfObjects; i++)
    {
        objects[i]->print();
    }
 
}
 
void ReadFile()
{
    char name[200];
    unsigned int year;
    float price;
    int number;
 
    numOfObjects = 0;
    fp = fopen("subjects.txt", "r");
    if (fp == NULL);
    {
        cout << "File not found!" << endl;
        return;
    }
    while (!feof(fp))
    {
        fgets(buf, 199, fp);
        cout << "buffer = " << buf << endl;
 
        number = sscanf(buf, "%s %s %d %f", name, &year, &price);
        cout << "number = " << number << endl;
        cout << "year = " << year << endl;
 
        if (number == 3)
        {
            // noai?eoe iauaeo eeano MathematicalSubject
            objects[numOfObjects++] = new MathematicalSubject( name, year);
        }
        if (number == 4)
        {
            // noai?eoe iauaeo eeano InformationSubject
            objects[numOfObjects++] = new InformationSubject( name, year, price);
        }
    }
    fclose(fp);
 
}
 
void WriteFile()
{
    fp = fopen("subjects.txt", "w");
    if (fp == NULL)
    {
        cout << "File not created!" << endl;
        return;
    }
    for (int i = 0; i < numOfObjects; i++)
    {
        objects[i]->write(fp);
    }
    fclose(fp);
}
 
void AddInformationSubject()
{
    char name[200];
    unsigned int year;
    float price;
 
    cout << "Input subjects name:";
    cin >> name;
    cout << "Input year of publishing:";
    cin >> year;
    cout << "Input price:";
    cin >> price;
    
    
    // noai?eoe iauaeo eeano InformationSubject
    objects[numOfObjects++] = new InformationSubject( name, year, price);
 
}
 
void AddMathematicalSubject()
{
    char name[200];
    unsigned int year;
 
 
    cout << "Input subjects name:";
    cin >> name;
    cout << "Input year of creation:";
    cin >> year;
    
    
    // noai?eoe iauaeo eeano MathematicalSubject
    objects[numOfObjects++] = new MathematicalSubject( name, year);
 
}
 
int main()
{
    short item;
 
    cout << "Hello World!\n" << endl;
 
    do
    {
        cout << "==MENU==" << endl;
        cout << "1. Read from file subject information" << endl;
        cout << "2. Output information in subjects " << endl;
        cout << "3. Add information about information subjects" << endl;
        cout << "4. Add information about mathematical subject " << endl;
        cout << "5. Write to file subjects " << endl;
        cout << "6. Exit" << endl;
    
        cout << "Input meny item: " << endl;
        cin >> item;
 
        switch (item)
        {
        case 1:
            ReadFile();
            break;
        case 2:
            Output();
            break;
        case 3:
            AddInformationSubject();
            break;
        case 4:
            AddMathematicalSubject();
            break;
        case 5:
            WriteFile();
            break;
        case 6:
            exit(0);
            break;
        default:
            cout << "Try another time..." << endl;
            break;
        };
    } while (true);
    return 0;
}