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

template<typename T1,typename T2> inline void chmin(T1 &a,T2 b){if(a>b) a=b;}
template<typename T1,typename T2> inline void chmax(T1 &a,T2 b){if(a<b) a=b;}

//INSERT ABOVE HERE
signed main(){
  string s,t;
  cin>>s>>t;
  s+=t;
  Int ans=0;
  Int n=s.size();
  for(Int i=0;i<n;i++){
    if(s[i]=='x') continue;
    Int j=i;
    while(j<n&&s[j]=='o') j++;
    chmax(ans,j-i);
  }
  cout<<ans<<endl;
  return 0;
}