#include <iostream>

using namespace std;

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