Word_in_Plural

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Word_in_Plural
{
    class Program
    {
        static void Main(string[] args)
        {
            string word = Console.ReadLine();

            string[] arr = new string[]
        {
            "o",
            "ch",
            "s",
            "sh",
            "x",
            "z"
        };

            foreach (string s in arr)
            {
                if (word.EndsWith(s))
                {
                    Console.WriteLine(word + "es");
                    return;
                }
            }

            if (word.EndsWith("y")) {
                word = word.Remove(word.Length - 1);
                Console.WriteLine(word + "ies");
            }
            else {
                Console.WriteLine(word + "s");
            }
        }
    }
}