#include <bits/stdc++.h>
using namespace std;

int main() {
    char c;
    int ans = 0, now = 0;
    for (int i = 0; i < 14; i++) {
        cin >> c;
        if (c == 'o') {
            now += 1;
            ans = max(ans, now);
        } else
            now = 0;
    }

    cout << ans << endl;
}