#include <iostream>
#include <string>
#include <algorithm>
using namespace std;

#define rep(i, n) for (int i = 0; i < n; i++)

int main()
{
	string S1, S2, C;
	cin >> S1 >> S2;
	C = S1 + S2;

	int ans = 0, cnt = 0, n = C.length();
	rep(i, n)
	{
		cnt = max(cnt, (int)(C[i] == 'o'));
		cnt = i != n && C[i] == 'o' && C[i] == C[i + 1] ? cnt + 1 : 0;
		ans = max(ans, cnt);
	}
	cout << ans << endl;
}