#include <iostream>
using namespace std;
int main() {
	char C[14];
	int ans = 0, count = 0;
	for (int i = 0; i < 14;i++) {
		cin >> C[i];
		if (C[i] == 'o') {
			count++;
		}
		else {
			ans = (ans > count) ? ans : count;
			count = 0;
		}
	}
	ans = (ans > count) ? ans : count;
	cout << ans << endl;
	return 0;
}