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using System;
using System.Text.RegularExpressions;
using System.Text;

class Program
{
    static void Main(string[] args)
    {
        StringBuilder input = new StringBuilder();
        input.Append(Console.ReadLine());
        MatchCollection matches = Regex.Matches(input.ToString(), @"<([a-zA-Z])([a-zA-Z])>");

        for (int i = 0; i < matches.Count; i++)
        {
            int firstDigit = Convert.ToInt32(char.Parse(matches[i].Groups[1].Value));
            int secondDigit = Convert.ToInt32(char.Parse(matches[i].Groups[2].Value));
            int power = Math.Abs(firstDigit - secondDigit);

            if (power > 0)
            {
                int startBefore = 0;
                int endAfter = 0;
                string before = null;
                string after = null;

                if (matches[i].Index + 1 >= power)
                {

                }

                for (int bf = matches[i].Index - power; bf <= matches[i].Index; bf++)
                {

                }


                input.Replace(before, new string('_', before.Length));
                input.Replace(after, new string('_', after.Length));
            }
            input.Replace(matches[i].ToString(), new string('_', 4));
        }

        Console.WriteLine(input.ToString());
    }
}