POO bilet nr 1 (partial nr1, nefacut de mine)

#include <iostream>                                                        //data calendaristica, bilet 1
#include<conio.h>
using namespace std;

class DataC
{
private:
    int zi;
    int luna;
    int an;

public:
    DataC();
    DataC(int zi, int luna, int an);
    DataC(const DataC &data);
    ~DataC();
    static bool validare(int zi, int luna, int an);
    void citire();
    void afisari();
    void afisare1();
    void afisare2();
    void afisare3();
};

DataC::DataC()
{
    zi = 1;
    luna = 1;
    an = 2000;
}

DataC::DataC(int zi, int luna, int an)
{
    this->zi = zi;
    this->luna = luna;
    this->an = an;
}

DataC::DataC(const DataC &data)
{
    zi = data.zi;
    luna = data.luna;
    an = data.an;
}

DataC::~DataC()
{

}

bool DataC::validare(int zi, int luna, int an)
{
    if ((luna == 2 && zi == 29 && an % 4 == 0)
        || (luna == 2 && zi == 28 && an % 4 == 1)
        || (luna % 2 == 0 && luna > 0 && luna <= 12 && luna != 2 && zi>0 && zi <= 30)
        || (luna % 2 == 1 && luna > 0 && luna <= 12 && zi>0 && zi <= 31))

        return true;
    else
        return false;
}
void DataC::citire()
{
    sus:
    cout << "Zi:"; cin >> zi;
    cout << "Luna:"; cin >> luna;

    cout << "An:"; cin >> an;
    if (!validare(zi, luna, an)) {
        system("cls");
        goto sus;
    }

}
void DataC::afisari()
{
    int format;
    cout << "Alegeti formatul afisarii:" << endl;
    cout << "1.zi/luna/an" << endl;
    cout << "2.luna/zi/an" << endl;
    cout << "3.an/luna/zi" << endl;
    cin >> format;
    if (format < 1 || format >3)
        cout << "Introduceti o optiune valida";

    if (format == 1)
        afisare1();
    if (format == 2)
        afisare2();
    if (format == 3)
        afisare3();
}

void DataC::afisare1()
{
    cout << "Data este: " << zi << "/" << luna << "/" << an;
}

void DataC::afisare2()
{
    cout << "Data este: " << luna << "/" << zi << "/" << an;
}

void DataC::afisare3()
{
    cout << "Data este: " << an << "/" << luna << "/" << zi;
}

int main()
{
    DataC data;
    data.citire();
    data.afisari();
    _getch();
    return 0;
}