#include <iostream>
#include <cstdio>
#define N 500005
using namespace std;

string a;
long long n, ans, i, s[N], l[N], r[N];
int main()
{
	cin >> a;
	n = a.size();
	for (i = 1; i <= n; i++) {
		if (a[i - 1] == '<') l[i] = l[i - 1] + 1;
		else l[i] = 0;
	}
	for (i = n - 1; i >= 0; i--) {
		if (a[i] == '>') r[i] = r[i + 1] + 1;
		else r[i] = 0;
	}
	for (i =0; i <= n; i++) ans += max(l[i], r[i]);
	cout << ans << endl;
    return 0;
}
