02. Odd Occurrences

using System;
using System.Collections.Generic;
using System.Linq;

namespace OddOccurrences
{
    class Program
    {
        public static void Main()
        {
            var oddCounts = Console.ReadLine()
                .ToLower()
                .Split(" ")
                .GroupBy(x => x)
                .ToDictionary(x => x.Key, x => x.Count())
                .Where(x => x.Value % 2 == 1)
                .Select(x => x.Key)
                .ToList();

            Console.WriteLine(string.Join(" ", oddCounts));
        }
    }
}