#include <iostream>
using namespace std;
int main(void) {
	int cntmax = 0, cnt = 0;
	char c;
	for (int i = 0; i < 14; ++i) {
		cin >> c;
		if (c == 'o') {
			++cnt;
			cntmax = max(cntmax, cnt);
		}
		else {
			cnt = 0;
		}
	}
	cout << cntmax << endl;
	return 0;
}