IEnumerable result = numbers.Distinct();

using System;
using System. Collections;
using System.Collections.Generic;
using System. Linq;
using System. Text;
using System.Threading.Tasks;
namespace ConsoleApp1
{
    class Programme2
    {
        static void Main(string[] args)
        {
//taking an array named countries type of string having the list of countries 
            string[] countries = { "UK", "India", "Australia", "uk", "india", "USA" };
//apply the Distinct method to find out the different country names 
            IEnumerable result = countries.Distinct(StringComparer.OrdinalIgnoreCase);
    //with the help of foreach loop fetch each element from the list of the array
            foreach (var item in result)
            {
    /*with the help of WriteLine() function print the values of 
    the variable item having the output of the result*/ 
                Console.WriteLine(item);
            }
                Console.ReadLine();
        }

    }

    }