public Assignment(Person person, int day, Shift shift)
{
Person = person ?? throw new ArgumentNullException(nameof(person));
Day = day;
Shift = shift ?? throw new ArgumentNullException(nameof(shift));
}
public Demand(int day, Shift shift, int requiredPeopleCount)
{
Day = day;
Shift = shift ?? throw new ArgumentNullException(nameof(shift));
RequiredPeopleCount = requiredPeopleCount;
}