public static void Exchange(Person a, Person b)
{
a._publicKey = a.ObtainThePublicKey(_g);
b._publicKey = b.ObtainThePublicKey(_g);
Console.WriteLine(a._publicKey);
Console.WriteLine(b._publicKey);
Swap(a, b);
a._publicKey = a.ObtainThePublicKey(a._publicKey);
b._publicKey = b.ObtainThePublicKey(b._publicKey);
Console.WriteLine(a._publicKey);
Console.WriteLine(b._publicKey);
}
