using System;
using System.Collections.Generic;

namespace _06._Replace_Repeating_Chars
{
    class Program
    {
        static void Main(string[] args)
        {
            string word = Console.ReadLine();

            string remove = RemoveDuplicateChars(word);
            Console.WriteLine(remove);
        }
        static string RemoveDuplicateChars(string word)
        {

            string result = "";

            foreach (char value in word)
            {
                if (result.IndexOf(value) == -1)
                {

                    result += value;
                }
            }
            return result;
        }
    }
}