#include <iostream>
#include <cstdlib>

using namespace std;

int main()
{
    int num;

    do
    {
        cout << "Inserisci un numero positivo: ";
        cin >> num;
    }
    while (num <= 0);

    cout << "Numeri pari da 2 a " << num << ": ";
    for (int i = 2; i <= num; i += 2)
        cout << i << " ";
    cout << endl;

    system("pause");
    return 0;
}