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

signed main(){
  string A, B; cin >> A >> B;
  string s = A + B;
  int ans = 0, cnt = 0;
  for( int i = 0; i < s.size(); ++i ){
    if( s[ i ] == 'o' )
      ans = max( ans, ++cnt );
    else
      cnt = 0;
  }
  cout << ans << endl;
  return 0;
}