import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		String[] weeks = new String[2];
		for (int i = 0; i < weeks.length; i++) {
			weeks[i] = sc.next();
		}
		char[] all = ("x" + weeks[0] + weeks[1] + "x").toCharArray();
		int cnt = 0;
		int max = 0;
		for (int i = 0; i < all.length; i++) {
			if (all[i] == 'o') {
				cnt++;
			} else {
				max = Math.max(max, cnt);
				cnt = 0;
			}
		}
		System.out.println(max);

	}
}