namespace ListExample

{

    using System.Collections.Generic;

​

    public class Program

    {

        private static readonly List<Animal> AnimalsToCheck = new List<Animal>

        {

            new Animal { Eater = Eater.Carnivore, Format = 1 },

            new Animal { Eater = Eater.Herbivore, Format = 3 }

        };

​

        private static readonly List<Wagon> Wagons = new List<Wagon>

        {

            new Wagon(

                1,

                5,

                1,

                new List<Animal>

                {

                    new Animal { Eater = Eater.Carnivore, Format = 5 },

                    new Animal { Eater = Eater.Herbivore, Format = 3 }

                }),

            new Wagon(

                2,

                9,

                5,

                new List<Animal>

                {

                    new Animal { Eater = Eater.Carnivore, Format = 1 }

                })

        };

​

        public static void Checker(List<Animal> listAnimals)

        {

            foreach (var animal in listAnimals)

            {

                // This is needed to not get an endless loop (Because the length of the list

                // increases after each time the Add() method is called to Wagons).

                var wagonCount = Wagons.Count;

​

                for (var i = 0; i < wagonCount; i++)

                {

                    var wagon = Wagons[i];

​

                    // This is needed to not get an endless loop (Because the length of the list

                    // increases after each time the Add() method is called to wagon.Animals).

                    var animalCount = wagon.Animals.Count;

​

                    for (var j = 0; j < animalCount; j++)

                    {

                        var wagonAnimal = wagon.Animals[j];

​

                        if (wagon.StartCapacity <= wagon.MaxCapacity

                            && animal.Format + wagon.StartCapacity <= wagon.MaxCapacity

                            && wagonAnimal.Eater == Eater.Carnivore && animal.Eater == Eater.Herbivore

                            && animal.Format >= wagonAnimal.Format)

                        {

                            wagon.Animals.Add(animal);

                            Wagons.Add(wagon);

                        }

                        else

                        {

                            var newWagon = new Wagon();

                            newWagon.Animals.Add(animal);

                            Wagons.Add(newWagon);

                        }

                    }

                }

​

                var wag = new Wagon();

                wag.Animals.Add(animal);

                Wagons.Add(wag);

            }

        }

​

        public static void Main()

        {

            Checker(AnimalsToCheck);

        }

    }

​

    public class Animal

    {

        public Eater Eater { get; set; }

​

        public int Format { get; set; }

    }

​

    public class Wagon

    {

        public List<Animal> Animals = new List<Animal>();

​

        public Wagon()

        {

        }

​

        public Wagon(int startCapacity, int maxCapacity, int format, List<Animal> animals)

        {

            this.StartCapacity = startCapacity;

            this.MaxCapacity = maxCapacity;

            this.Format = format;

            this.Animals = animals;

        }

​

        public int Format { get; set; }

​

        public int MaxCapacity { get; set; }

​

        public int StartCapacity { get; set; }

    }

​

    public enum Eater

    {

        Carnivore,

​

        Herbivore

    }

}