#include <bits/stdc++.h>

using namespace std;

#define REP(i,n) for(int i=0; i<(int)(n); i++)
#define FOR(i,b,e) for (int i=(int)(b); i<(int)(e); i++)
#define ALL(x) (x).begin(), (x).end()

const double PI = acos(-1);

int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);

  string t;
  REP (i, 2) {
    string s;
    cin >> s;
    t += s;
  }
  
  int ret = 0;
  REP (i, 14) {
    string target(i+1, 'o');
    if (t.find(target) != string::npos)
      ret = i+1;
  }
  cout << ret << endl;
  
  return 0;
}