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

namespace ProgrammingContest
{
    class MainClass
    {
        Scanner sc;
        static void Main(string[] args)
        {
            new MainClass().Solve();
        }

        void Solve()
        {
#if DEBUG
            string backPath = "..";
            char dirSep = System.IO.Path.DirectorySeparatorChar;
            string inFilePath = backPath + dirSep + backPath + dirSep + "in.txt";
            sc = new Scanner(new System.IO.StreamReader(inFilePath));
#else
            sc = new Scanner();
#endif

            string s = sc.Next;
            List<Tuple<string, int>> list = new List<Tuple<string, int>>();
            {
                string buf = string.Empty;
                int wCnt = 0;
                foreach (var c in s)
                {
                    if (c == 'ｗ')
                    {
                        if (!string.IsNullOrEmpty(buf))
                        {
                            wCnt++;
                        }
                    }
                    else
                    {
                        if (wCnt > 0)
                        {
                            list.Add(Tuple.Create(buf, wCnt));
                            buf = string.Empty;
                            wCnt = 0;
                        }
                        buf += c;
                    }
                }
                if (!string.IsNullOrEmpty(buf) && wCnt > 0)
                {
                    list.Add(Tuple.Create(buf, wCnt));
                }
            }
            int ma = 0;
            foreach (var el in list)
            {
                if (ma < el.Item2)
                {
                    ma = el.Item2;
                }
            }
            foreach (var el in list)
            {
                if (ma == el.Item2)
                {
                    Write(el.Item1);
                }
            }
        }

        void Write(object val)
        {
            Console.WriteLine(val.ToString());
        }
        void Write(string format, params object[] vals)
        {
            Console.WriteLine(format, vals);
        }
    }
    
    class Scanner
    {
        Queue<String> buffer;
        char[] sep;
        System.IO.TextReader reader;
        public Scanner(System.IO.TextReader reader = null)
        {
            this.buffer = new Queue<string>();
            this.sep = new char[] { ' ' };
            this.reader = (reader ?? Console.In);
        }
        private void CheckBuffer()
        {
            if (this.buffer.Count == 0 && this.reader.Peek() >= 0)
            {
                string[] sreArray = this.reader.ReadLine().Split(this.sep);
                foreach (String elStr in sreArray)
                {
                    this.buffer.Enqueue(elStr);
                }
            }
        }

        public String Next
        {
            get
            {
                this.CheckBuffer();
                return this.buffer.Dequeue();
            }
        }

        public int NextInt
        {
            get
            {
                return int.Parse(this.Next);
            }
        }
        public double NextDouble
        {
            get
            {
                return double.Parse(this.Next);
            }
        }

        public long NextLong
        {
            get
            {
                return long.Parse(this.Next);
            }
        }
        public bool IsEmpty
        {
            get
            {
                this.CheckBuffer();
                return this.buffer.Count == 0;
            }
        }
    }
}