#include <bits/stdc++.h>

using namespace std;

#define REP(i, n) for(int i = 0; i < n; i++)

int main() {
    int ans = 0, cnt = 0;
    REP(i, 14) {
        char c;
        cin >> c;
        if (c == 'o') {
            cnt++;
            ans = max(ans, cnt);
        } else {
            cnt = 0;
        }
    }
    
    cout << ans << endl;
    return 0;
}