#include <iostream>

using namespace std;
using LL = long long;

int main() {
    string C1, C2, C;
    cin >> C1 >> C2;
    C = C1 + C2;

    int ans = 0, count = 0;
    for (int i = 0; i < 14; i++) {
        if (C[i] == 'x') count = 0;
        else ans = max(ans, ++count);
    }
    cout << ans << endl;
}