using System;

using System.Linq;

using System.Collections.Generic;

​

namespace ZooProblem {

    public class Animals {

        public Dictionary<string, List<string>> ZooAnimals = new Dictionary<string, List<string>>();

​

        public Animals() {

            ZooAnimals.Add("antelope", new List<string>(){"grass"});

            ZooAnimals.Add("big-fish", new List<string>(){"litte-fish"});

            ZooAnimals.Add("bug", new List<string>(){"bug", "leaves"});

            ZooAnimals.Add("bear", new List<string>(){"big-fish", "bug", "chicken", "cow", "leaves", "sheep"});

            ZooAnimals.Add("chicken", new List<string>(){"bug"});

            ZooAnimals.Add("cow", new List<string>(){"grass"});

            ZooAnimals.Add("fox", new List<string>(){"chicken", "sheep"});

            ZooAnimals.Add("giraffe", new List<string>(){"leaves"});

            ZooAnimals.Add("lion", new List<string>(){"antelope", "cow"});

            ZooAnimals.Add("panda", new List<string>(){"leave"});

            ZooAnimals.Add("sheep", new List<string>(){"grass"});

        }

    }

​

    public class Program {

        public static List<string> eatingOutput = new List<string>();

​

        public static void Main() {

            Console.WriteLine("Please enter your list of animals");

            string input = Console.ReadLine();

            List<string> animalList = input.Split(',').ToList();

            List<string> output = new List<string>();

            output.Add(string.Join(",", animalList));

            Program.EatEverythingPossible(animalList);

            output.AddRange(Program.eatingOutput);

            output.ForEach(i => Console.WriteLine(i));

        }

​

        static public void EatEverythingPossible(List<string> animalList) {

            //int currentZooCount = 0;

            for(int i = 0; i < animalList.Count(); i++) {

                animalList = LeftHandEatingRule(animalList, animalList[i]);

                animalList = RightHandEatingRule(animalList, animalList[i]);

            }

            /*

            while (currentZooCount != animalList.Count()) {

                currentZooCount = animalList.Count();

                animalList = LeftHandEatingRule(animalList);

                animalList = RightHandEatingRule(animalList);

            }

            */

            /*

            currentZooCount = 0;

            while (currentZooCount != animalList.Count()) {

                currentZooCount = animalList.Count();

                animalList = RightHandEatingRule(animalList);

            }

            */

            Program.eatingOutput.Add(string.Join(",", animalList));

        }

​

        static public List<string> RightHandEatingRule(List<string> animalList, string animal) {

            Dictionary<string, List<string>> zooAnimals = new Animals().ZooAnimals;

            int index = animalList.FindIndex(x => x.Contains(animal));

            string currentAnimal = animalList[index];

            for(int j = index + 1; j < animalList.Count(); j++) {

                    if (zooAnimals.ContainsKey(currentAnimal) && zooAnimals[currentAnimal].Contains(animalList[j])) {

                        Program.eatingOutput.Add(string.Format("{0} eats {1}", currentAnimal, animalList[j]));

                        animalList.RemoveAt(j);

                        return animalList;

                    }

                }

            /*

            for(int i = 0; i < animalList.Count(); i++) {

                string currentAnimal = animalList[i];

                for(int j = i + 1; j < animalList.Count(); j++) {

                    if (zooAnimals.ContainsKey(currentAnimal) && zooAnimals[currentAnimal].Contains(animalList[j])) {

                        Program.eatingOutput.Add(string.Format("{0} eats {1}", currentAnimal, animalList[j]));

                        animalList.RemoveAt(j);

                        return animalList;

                    }

                }

            }

            */

            return animalList;

        }

​

        static public List<string> LeftHandEatingRule(List<string> animalList, string animal) {

            Dictionary<string, List<string>> zooAnimals = new Animals().ZooAnimals;

            int index = animalList.FindIndex(x => x.Contains(animal));

            string currentAnimal = animalList[index];

            for(int j = 0; j < index; j++) {

                    if (zooAnimals.ContainsKey(currentAnimal) && zooAnimals[currentAnimal].Contains(animalList[j])) {

                        Program.eatingOutput.Add(string.Format("{0} eats {1}", currentAnimal, animalList[j]));

                        animalList.RemoveAt(j);

                        return animalList;

                    }

            }

            /*

            for(int i = 0; i < animalList.Count(); i++) {

                string currentAnimal = animalList[i];

                for(int j = 0; j < i; j++) {

                    if (zooAnimals.ContainsKey(currentAnimal) && zooAnimals[currentAnimal].Contains(animalList[j])) {

                        Program.eatingOutput.Add(string.Format("{0} eats {1}", currentAnimal, animalList[j]));

                        animalList.RemoveAt(j);

                        return animalList;

                    }

                }

            }

            */

            return animalList;

        }

    }

​

}