Комментарии к каждой строчки программы

#include <iostream>
#include <cstring>
using namespace std;
 
char* StrDup(const char* src) {
 
    char* dest = new char[std::strlen(src) + 1];
    return strcpy(dest, src);
}
 
class Personnel {
    
public:
    Personnel();
    Personnel(const char* name, int age, int staj);
    Personnel(const Personnel& rhs);
 
    ~Personnel();
 
    void SetName(const char* name);
    void SetAge(int age);
    void SetStaj(int staj);
 
    const char* GetName() const;
    int GetAge() const;
    int GetStaj() const;
    
private:
    char* name_;
    int age_;
    int staj_;
};
 
Personnel::Personnel() {
 
    name_ = StrDup("unnamed");
    age_ = 0;
    staj_ = 0;
 
    cout << "Personnel()" << std::endl;
}
 
Personnel::Personnel(const char* name, int age, int staj) {
 
    name_ = StrDup(name);
    age_ = age;
    staj_ = staj;
 
    cout << "Personnel(const char*, int, int)" << std::endl;
}
 
Personnel::Personnel(const Personnel& rhs) {
 
    name_ = StrDup(rhs.name_);
    age_ = rhs.age_;
    staj_ = rhs.staj_;
 
    cout << "Personnel(const Personnel&)" << std::endl;
}
 
Personnel::~Personnel() {
 
    delete[] name_;
    
    cout << "~Personnel()" << std::endl;
}
 
void Personnel::SetName(const char* name) {
 
    delete[] name_;
    name_ = NULL;
    name_ = StrDup(name);
}
 
void Personnel::SetAge(int age) {
 
    age_ = age;
}
 
void Personnel::SetStaj(int staj) {
 
    staj_ = staj;
}
 
const char* Personnel::GetName() const {
 
    return name_;
}
 
int Personnel::GetAge() const {
 
    return age_;
}
 
int Personnel::GetStaj() const {
 
    return staj_;
}
 
void show_info(const Personnel& personnel) {
 
    cout << "Name: " << personnel.GetName() << '\n';
    cout << "Age: " << personnel.GetAge() << '\n';
    cout << "Staj: " << personnel.GetStaj() << '\n';
    cout << std::endl;
}
 
int main() {    
    
    cout << "personnel1 -> "; 
    Personnel* personnel1 = new Personnel();
 
    cout << "personnel2 -> ";
    Personnel* personnel2 = new Personnel("personnel2", 2, 2);
 
    cout << "personnel3 -> ";
    Personnel* personnel3 = new Personnel(*personnel2);
    
    cout << "\n...\n" << std::endl;    
    
    void (Personnel::*SetName_ptr)(const char*) = &Personnel::SetName;
    
    (personnel1->*SetName_ptr)("personnel1");
    personnel1->SetAge(1);
    personnel1->SetStaj(1);
    
    (personnel3->*SetName_ptr)("personnel3");
 
    show_info(*personnel1);
    show_info(*personnel2);
    show_info(*personnel3);
    
    cout << "...\n" << std::endl;
 
    cout << "personnel1 -> "; 
    delete personnel1;
 
    cout << "personnel2 -> ";
    delete personnel2;
 
    cout << "personnel3 -> ";
    delete personnel3;    
 
    system("pause");
}