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