import java.util.Scanner;
import java.util.ArrayList;

class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        ArrayList<Character> al = new ArrayList<Character>();
        String s = sc.next();
        for (char c : s.toCharArray()) al.add(c);
        s = sc.next();
        for (char c : s.toCharArray()) al.add(c);

        int i, c = 0, h = 1, m = 0;
        char f;
        for (i = 0; i < al.size(); i++) {
            f = al.get(i);
            if (f == 'x') {
                h = 0;
                if (m < c) m = c;
                c = 0;
            } else c++;
        }
        System.out.printf("%d\n", m);
    }
}