#include <bits/stdc++.h>
#define FOR(i,a,b) for(int i = (a); i < (b); ++i)
#define REP(i,n) FOR(i,0,n)
#define SZ(n) (int)(n).size()
using namespace std;
typedef long long ll;
typedef vector<int> VI;

int main() {
	VI c;
	REP(i, 14) {
		char t;
		cin >> t;
		c.push_back(t);
	}
	int ans = 0;
	int cnt = 0;
	REP(i, 14) {
		if (c[i] == 'o') {
			cnt++;
			ans = max(ans, cnt);
		}
		else {
			cnt = 0;
		}
	}
	cout << ans << endl;
	return 0;
}