public class Animal {
        public Animal() {
            AnimalType = (AnimalType)AnimalTypeValues.GetValue(Random.Next(AnimalTypeValues.Length));
            EatenFood = new List<FoodType>();
        }
        public AnimalType AnimalType { get; set; }
        public List<FoodType> EatenFood { get; set; }
        private static readonly Array AnimalTypeValues = Enum.GetValues(typeof(AnimalType));
        private static readonly Random Random = new Random();
        public static readonly Dictionary<AnimalType, List<FoodType>> AnimalFoods = new Dictionary<AnimalType, List<FoodType>> {
            { AnimalType.Mouse, new List<FoodType> { FoodType.Cheese, FoodType.Rusk } },
            { AnimalType.Cat, new List<FoodType> { FoodType.Milk, FoodType.Meat } },
            { AnimalType.Dog, new List<FoodType> { FoodType.Meat, FoodType.Rusk } },
        };
    }
    public enum AnimalType { Unknown, Mouse, Cat, Dog }
    public enum FoodType { Unknown, Milk, Meat, Cheese, Rusk }
    public static class Prog {
        public static void Main() {
            Console.WriteLine("Foods before feed: " + String.Join(",", Foods));
            FeedAnimals();
            Console.WriteLine("Foods after feed: " + String.Join(",", Foods));

            Console.WriteLine("Feed results: ");
            foreach(Animal animal in Animals) {
                Console.WriteLine(animal.AnimalType + " ate: " + String.Join(",", animal.EatenFood));
            }
        }
        private static readonly Array FoodTypeValues = Enum.GetValues(typeof(FoodType));
        private static readonly Random Random = new Random();
        private static readonly List<Animal> Animals = Enumerable.Repeat(new Animal(), 10).ToList();
        private static readonly List<FoodType> Foods = Enumerable.Repeat((FoodType)FoodTypeValues.GetValue(Random.Next(FoodTypeValues.Length)), 50).ToList();
        private static void FeedAnimals() {
            Animals.ForEach(x => {
                FoodType food = Foods.FirstOrDefault(y => Animal.AnimalFoods[x.AnimalType].Contains(y));
                if(food != FoodType.Unknown) {
                    x.EatenFood.Add(food);
                    Foods.Remove(food);
                }
            });
        }
    }