using System;

namespace АучDeleter
{
    class Program
    {
        public static string s { get; set; }
        public static string A = "Ауч";
        public static int a;
        public static int y;
        public static int ch;
        static void Main(string[] args)
        {
            Console.WriteLine("Введите сообщение");
            s = Console.ReadLine();
            Console.WriteLine(Deleter(s));
        }
        public static string Deleter(string s)
        {
            if (s.Contains(A) || s.Contains(A.ToLower()) || s.Contains(A.ToUpper()))
            {
                s = null;
                return s;
            }
            if (s.Contains("А") || s.Contains("а") || s.Contains("У") || s.Contains("у") || s.Contains("Ч") || s.Contains("ч"))
            {
                char[] chars = s.ToCharArray();
                for (int i = 0; i < chars.Length; i++)
                {
                    if (chars[i] == 'А' || chars[i] == 'а' ) a = i;
                    if (chars[i] == 'У' || chars[i] == 'у') y = i;
                    if (chars[i] == 'Ч' || chars[i] == 'ч') ch = i;
                    if (Math.Abs(a - y) >= 1 || Math.Abs(a - ch) >= 1 || Math.Abs(y - ch) >= 1)
                    {
                        s.Insert(a, "");
                        s.Insert(y, "");
                        s.Insert(ch, "");
                    }
                }
            }
            return s;
        }
    }
}