/// <summary>
/// Chooses shortest line and stands on it.
/// Also it calls cashier's method StandOnLine which adds him to queue.
/// </summary>
/// <param name="cashiers"></param>
public void StandOnLine(List <ICashier> cashiers)
{
ICashier chosenCachier = cashiers.OrderBy(cashier => cashier.LineCount).First();
chosenCachier.StandOnLine(this);
}
