Создание/удаление объектов класса - C++ - Ответ 10305021

#ifndef COW_H
#define COW_H
 
class Cow
{
private:
    char name[20];
    char * hobby;
    double weight;
    static int num;
 
public:
    Cow();
    Cow(const char * nm, const char * ho, double wt);
    Cow(const Cow & c);
    ~Cow();
    Cow & operator = (const Cow & c);
    void ShowCow() const;
};
 
#endif

#include <iostream>
#include <cstring>
#include "cow.h"
int Cow::num = 0;
 
Cow::Cow()
{
    num++;
    std::strcpy(name, "NULL-cow");
    hobby = new char[1];
    hobby[0] = '\0';
    weight = 0;
}
 
Cow::Cow(const char *nm, const char *ho, double wt)
{
    num++;
    std::strcpy(name, nm);
    int len = std::strlen(ho);
    hobby = new char[len+1];
    std::strcpy(hobby, ho);
    weight = wt;
}
 
Cow::Cow(const Cow &c)
{
    num++;
    std::strcpy(name, c.name);
    int len = std::strlen(c.hobby);
    hobby = new char[len+1];
    std::strcpy(hobby, c.hobby);
    weight = c.weight;
}
 
Cow::~Cow()
{
    std::cout << "\n\nObject " << name << " was delete, " << num - 1 << " remain." << std::endl;;
    num--;
    delete []hobby;
}
 
Cow & Cow::operator =(const Cow &c)
{
    if (this == &c)
        return *this;
    delete []hobby;
    int len = std::strlen(c.hobby);
    hobby = new char[len+1];
    std::strcpy(hobby, c.hobby);
    std::strcpy(name, c.name);
    return *this;
}
 
void Cow::ShowCow() const
{   std::cout << "Name: " << name << ", hobby: " << hobby << ", weight: " << weight << std::endl;           }

#include <iostream>
#include "cow.h"
 
int main()
{
    Cow a;
    a.ShowCow();
    Cow b("RED-cow", "gryuzet", 5);
    b.ShowCow();
 
    Cow * c = new Cow;
    c -> ShowCow();
    c ->~Cow();
    return 0;
}

a.ShowCow();