我一直在Turbo C ++中编写有关多重继承的代码，代码的目的是仅获取输入并在控制台上打印输入。我最初完成了以下代码，

// Program to demonstrate multiple inheritance

#include <conio.h>
#include <iomanip.h>
#include <iostream.h>
#include <stdio.h>
#include <stdlib.h>>
#include <string.h>

class Company1
{
protected:
  int productID;
  char *productName;
  char *CompanyName;

public:
  void input_c1()
  {
    cout << "Provide Company 1 Details : " << endl;
    cout << setw(29) << setfill('-') << "" << endl;
    cout << "Enter the Product ID : ";
    cin >> productID;
    cout << "Enter the Product Name : ";
    gets(productName);
    cout << "Enter the Company Name : ";
    gets(CompanyName);
  }
};

class Company2
{
protected:
  int productID;
  char *productName;
  char *CompanyName;

public:
  void input_c2()
  {
    cout << endl << "Provide Company 2 Details : " << endl;
    cout << setw(29) << setfill('-') << "" << endl;
    cout << "Enter the Product ID : ";
    cin >> productID;
    cout << "Enter the Product Name : ";
    gets(productName);
    cout << "Enter the Company Name : ";
    gets(CompanyName);
  }
};

class SuperMarket : public Company2,public Company1
{
public:
  void Company_details()
  {
    cout << endl << "Company 1 details : " << endl;
    cout << setw(20) << setfill('-') << "" << endl;
    cout << "Product ID   : " << Company1::productID << endl;
    cout << "Product Name : ";
    print_string(Company1::productName);
    cout << endl;
    cout << "Company Name : ";
    print_string(Company1::CompanyName);
    cout << endl << endl;

    cout << "Company 2 details : " << endl;
    cout << setw(20) << setfill('-') << "" << endl;
    cout << "Product ID   : " << Company2::productID << endl;
    cout << "Product Name : ";
    print_string(Company2::productName);
    cout << endl;
    cout << "Company Name : ";
    print_string(Company2::CompanyName);
  }
  void print_string(char *ptr)
  {
    for (int i = 0; i != strlen(ptr); i++)
      cout << ptr[i];
  }
};

void main()
{
  char choice;
  clrscr();
  SuperMarket s;
  s.input_c1();
  s.input_c2();
  s.Company_details();
  cout << endl << "Do you want to exit ? (Y/N) : ";
  cin >> choice;
  if (choice == 'Y' || choice == 'y')
    exit(0);
  getch();
}

执行后得到如下输出

但这不是预期的输出，因为 Company1 的 Company Name 为 dklm ，而预期为 def 。我进一步尝试纠正它，并将 Company1 的派生类型设置为虚拟公共，这导致正确的输出。听说虚拟主要用于钻石问题。尽管不是 Diamond问题，但它可以产生正确的输出。谁能解释为什么我在提到的程序中得到了这样的错误输出？在这种情况下，虚拟机如何使程序正常工作？