#include <iostream>
#include <string>
#include <algorithm>
#include <functional>
#include <vector>
#include <stack>
#include <queue>
#include <set>
#include <map>
#include <tuple>
#include <cstdio>
#include <cmath>
#include <cassert>
#define rep(i, n) for(i = 0; i < n; i++)
#define int long long
using namespace std;

signed main() {
    string s;
    cin >> s;

    typedef pair<char, int> P;
    vector<P> stk;

    for (int i = 0; i < s.length(); i++) {
        if (s[i] == '<' || s[i] == '>') {
            stk.push_back(P(s[i], 1));
        }
        else {
            if (stk.size() > 0 && stk[stk.size() - 1].first == '=') stk[stk.size() - 1].second++;
            else stk.push_back(P(s[i], 1));
        }
        if (stk.size() >= 3 && stk[stk.size() - 3].first == '<' && stk[stk.size() - 2].first == '=' && stk[stk.size() - 1].first == '>') {
            stk.pop_back();
            stk.pop_back();
            stk.pop_back();
        }
    }

    int ans = 0, i;
    rep(i, stk.size()) {
        ans += stk[i].second;
    }

    cout << ans << endl;
    return 0;
}