public static int DisplayMenu(ApeService apeService) { Console.WriteLine(""); Console.WriteLine("--------------------------------"); Console.WriteLine("Welcome to Shan Family Tree"); Console.WriteLine("These are the total list of apes , please use exact names"); foreach (Ape ape in apeService.GetAll()) { Console.Write(ape.GetName() + $"\t"); } Console.WriteLine(); Console.WriteLine("These are the total list of Relations , please use exact names"); foreach (var relationship in Enum.GetNames(typeof(RelationshipType))) { Console.Write(relationship + $"\t"); } Console.WriteLine(); Console.WriteLine("1. Get Relations of Ape"); Console.WriteLine("2. Add a NewBorn into Family"); Console.WriteLine("3. Find Mother with Maximum number of Girl Childs"); Console.WriteLine("4. Find Relation between two Apes"); Console.WriteLine("5. Exit"); var result = Console.ReadLine(); int input; if (Int32.TryParse(result, out input)) { return(input); } return(5); }