#include <iostream>
#include <string>
#include <vector>
#include <algorithm>
using namespace std;

int main()
{
	int cnt = 0;
	int ans = 0;
	for (int i = 0; i < 14; i++) {
		char c;
		cin >> c;
		if (c == 'o') cnt++;
		else {
			ans = max(cnt, ans);
			cnt = 0;
		}
	}
	ans = max(cnt, ans);

	cout << ans << endl;

    return 0;
}