using System.Collections.Generic;
using System;

public class Hello
{
    static void Main()
    {
        var s = Console.ReadLine().Trim();
        getAns(s);
    }
    static void getAns(string s)
    {
        var st = new Stack<int>();
        var a = getQ(s);
        foreach (var x in a)
        {
            if (x == 0) st.Push(x);
            else if (x <0)
            {
                if (st.Count == 0) { st.Push(x); continue; }
                if (st.Peek() < 0)
                {
                    var ww = st.Pop();
                    ww += x;
                    st.Push(ww);
                }
                else st.Push(x);
            }
            else
            {
                if (st.Count == 0) { st.Push(1); continue; }
                if (st.Peek() < 0)
                {
                    var w = st.Pop();
                    if (st.Count == 0) { st.Push(w);  continue; }
                    if (st.Peek() == 0) st.Pop();
                    else { st.Push(w); st.Push(x); }
                }
                else st.Push(x);
            }
        }
        var ans = 0;
        foreach (var x in st)
        {
            if (x >= 0) ans++;
            else ans += -x;
        }
        Console.WriteLine(ans);
    }
    static int[] getQ(string s)
    {
        var n = s.Length;
        var q = new Queue<int>();
        var f = false;
        var c = 0;
        if (s[0] == '<') q.Enqueue(0);
        else if (s[0] == '>') q.Enqueue(1);
        else { f = true; c = 1; }
        for (int i = 1; i < n; i++)
        {
            if (s[i] == '=')
            {
                if (f) c++;
                else { f = true; c = 1; }
            }
            else
            {
                f = false;
                if (c > 0) { q.Enqueue(-c); c = 0; }
                if (s[i] == '<') q.Enqueue(0);
                else q.Enqueue(1);
            }
        }
        if (f) q.Enqueue(-c);
        return q.ToArray();
    }
}