static void Main() { Dog dogNinja = new Dog("Stamat", 6, Sex.Male); dogNinja.Sound(); Kitten kotence = new Kitten("Eli", 1, Sex.Female); // This will throw exeption // Kitten kotence = new Kitten("Eli", 1, Sex.Male); List <Animal> animalList = new List <Animal>(); animalList.Add(new Frog("Stamat", 2, Sex.Male)); animalList.Add(new Tomcat("Stamat", 1, Sex.Male)); animalList.Add(new Dog("Stamat", 3, Sex.Male)); animalList.Add(new Kitten("Stamat", 5, Sex.Female)); animalList.Add(new Frog("Stamat", 7, Sex.Male)); animalList.Add(new Tomcat("Stamat", 12, Sex.Male)); animalList.Add(new Dog("Stamat", 65, Sex.Male)); animalList.Add(new Kitten("Stamat", 47, Sex.Female)); animalList.Add(new Frog("Stamat", 12, Sex.Male)); animalList.Add(new Tomcat("Stamat", 36, Sex.Male)); animalList.Add(new Dog("Stamat", 48, Sex.Male)); animalList.Add(new Kitten("Stamat", 16, Sex.Female)); animalList.Add(new Frog("Stamat", 42, Sex.Male)); animalList.Add(new Tomcat("Stamat", 36, Sex.Male)); animalList.Add(new Dog("Stamat", 71, Sex.Male)); animalList.Add(new Kitten("Stamat", 30, Sex.Female)); int averageAge = Animal.AverageAge(animalList); Console.WriteLine("The average age of all animals is: {0}", averageAge); }