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

namespace yukikoda
{
    class Program
    {
        static void Main(string[] args)
        {
            string s = Console.ReadLine();
            var li = new List<string>();
            int max = 0;

            string w = "";

            int cnt = 0;
            for (int i = 0; i < s.Length; i++)
            {
                if (s[i] == 'ｗ')
                {
                    cnt = 0;
                    for (int j = i; j < s.Length; j++)
                    {
                        if (s[j] == 'ｗ') cnt++;
                        else break;
                    }

                    if (cnt > max && w.Length != 0)
                    {
                        max = cnt;
                        li.Clear();
                    }

                    if (cnt == max && w.Length != 0)
                    {
                        li.Add(w);
                    }
                    w = "";
                }
                else
                {
                    w += s[i];
                }
            }

            foreach (var item in li)
            {
                Console.WriteLine(item);
            }
        }
    }
}