#include <iostream>

using namespace std;

int main(void) {
	std::ios::sync_with_stdio(false);
	std::cin.tie(0);
	int max = 0;
	int cnt = 0;
	char C;
	for (int i = 0; i < 14; i++) {
		cin >> C;
		if (C == 'o') {
			cnt++;
			if (cnt > max) {
				max = cnt;
			}
		} else {
			cnt = 0;
		}
	}
	cout << max << endl;
}