// #define _GLIBCXX_DEBUG
#include <bits/stdc++.h>
using namespace std;
#define rep(i, n) for (int i = 0; i < (int)(n); ++i)
string runLength(const string& s) {
    string t;
    char c = '\0';
    int cnt = 0;
    for (int i = 0; i <= s.size(); ) {
        if (c != s[i]) {
            if (cnt > 0) t += c + to_string(cnt);
            cnt = 0;
            c = s[i];
        } else ++i, ++cnt;
    }
    return t;
}
int main() {
    // Input
    string s;
    char c;
    rep(i, 14) { cin >> c; s += c; }

    // Calculate
    int x, ans = 0;
    stringstream ss(runLength(s));
    while (ss >> c >> x) if (c == 'o') ans = max(ans, x);

    // Output
    cout << ans << endl;
}