simple family tree in c++ using pointers

Question

I'm trying to create a simple family tree in C++ by utilizing pointers in order to input strings for names that are then saved step-by-step within the code.

For example, the program starts at an unknown spot, and the user is prompted to either enter a name for the current spot, move to the dad's spot, move to the mom's spot, or go back to the starting person (first person registered). This is what I've got so far:

#include <iostream>
#include <cstdlib>
using namespace std;

class person
{
public:
    person* mom;
    person* dad;
    string name;
    person();
    ~person();
    person(string n);
};


person::person()
{
    mom = nullptr;
    dad = nullptr;
    name = "Unknown";
}    

person::~person()
{
//delete any dynamic memory if needed
}

person::person(string n)
{
    name = n;
}

int main()
{
string inputName;
person current;
person *pointer; //I know I'll probably need to use a class pointer 
//in some manner to keep track of the current pointer, but how?
//also, how to turn private variables in person into public
//while still being able to use them indirectly in main, if possible? 

char choice;
do {
    cout << "You are currently at: " << current.name << endl;
    cout << "Your mom is: ";
    if(current.mom == nullptr)
    {
        cout << "???" << endl;
    }
    else
    {
        cout << current.mom;
    }
    cout << "Your dad is: ";
    if(current.dad == nullptr)
    {
        cout << "???" << endl;
    }
    else
    {
        cout << current.dad;
    }
    cout << "Give name, go to mom, go to dad, back to start, or quit?" << endl;
    cin >> choice;

    if (choice == 'g')
    {
        cout << "What name (single word)?" << endl;
        cin >> inputName;
        current.name = inputName;
    }
    else if (choice == 'm')
    {
    //go to mom spot
    }
    else if (choice == 'd')
    {
    //go to dad spot
    }
    else if (choice == 'b')
    {
    //go to first registered name
    }
}
while (choice == 'g' || choice == 'm' || choice == 'd' || choice == 'b');
//else quit
return 0;
}

My code is quite sloppy at the moment, as I'm a complete beginner to C++ and only started about a week ago on my own. I know public variables are a really bad practice, but I don't really know how to use private variables within main. Any help with how to organize my pointers or how to make private variables work within main would be greatly appreciated.

Answer 1

You declared and defined your class' public members correctly, to implement the private ones you do not need to change too much.

Under your class definition, you simply need to include a "private:" section as well. You declare your private variables or functions under there, and the getters and setters for these variables under the public header.

so your

class person
{
public:
    person* mom;
    person* dad;
    string name;
    person();
    ~person();
    person(string n);
};

Becomes

class person
{
public:
    person();
    ~person();
    person(string n);

    void setName(string);

    person* getMom();
    person* getDad();
    string getName();
private:
    person* mom;
    person* dad;
    string name;
};

Note that when declaring a function, you do not need to provide the name of any parameter variables. That is completely optional; the compiler only need know what type of variable to expect.

Then, just like how you defined your constructors and destructor, you define the getters and setters you just declared.

...
person::person(string n)
{
    name = n;
}

void person::setName(string name)
{
    this->name = name;
}

person* person::getMom()
{
    return mom;
}

person* person::getDad()
{
    return dad;
}

string person::getName()
{
    return name;
}

int main()
...

This formatting is essentially the same as if you were to separate the Person class into its own header (.h) and cpp (.cpp) files.

Then, to access your private members you need only call the getters or setters you just created. So,

cout << "You are currently at: " << current.name << endl;

Becomes

cout << "You are currently at: " << current.getName() << endl;

Hope that makes sense.

ps: If you're using C++'s string class you may want to #include <string>

pps: Its good practice to always capitalize the first letter of whatever class you are making. Just so it stands out. Person instead of person.