using namespace std;
#include <bits/stdc++.h>
#define BEGIN ios_base::sync_with_stdio(0);cin.tie(0);
#define END return EXIT_SUCCESS;
#define FOR(I,A,B) for(int (I)=(A);(I)<(B);++(I))
#define ALL(C) (C).begin(),(C).end()
void solve()
{
	string S,T;int A=0,D[15]={};
	cin>>S>>T;S+=T;
	FOR(i,0,14)if(S[i]=='o')A=max(A,D[i+1]=D[i]+1);
    cout<<A<<endl;
}
int main(int argc,char**argv)
{
	BEGIN
	solve();
	END
}