private void ButtonAgeRabbitsClick(object sender, RoutedEventArgs e)
 {
     for (int i = 0; i < 100; i++)
     {
         var rabbit = new Rabbit();
         rabbit.age        = 0;
         rabbit.rabbitName = "Rabbit" + i;
         rabbitList.Add(rabbit);
     }
     foreach (var i in rabbitList)
     {
         i.age += 50;
         ListAgeRabbits.Items.Add(i.rabbitName + " " + i.age);
     }
 }
        private void ButtonGenRabbits100TimesClick(object sender, RoutedEventArgs e)
        {
            for (int i = 0; i < 100; i++)
            {
                var rabbit = new Rabbit();
                rabbit.age        = 0;
                rabbit.rabbitName = "Rabbit" + i;
                rabbitList.Add(rabbit);
            }

            foreach (var rabbit in rabbitList)
            {
                List100Rabbits.Items.Add(rabbit.rabbitName);
            }
        }