import java.util.*;

class Ideone{
	public static void main (String[] args) throws java.lang.Exception
	{
		Scanner koko = new Scanner(System.in);
		String one = koko.next();
		String two = koko.next();
		String whole = one + two;
		String[] who = whole.split("x");
		int[] week = new int[who.length];
		for(int i=0; i<who.length; i++){
			week[i]=who[i].length();
		}
		Arrays.sort(week);
		System.out.println(week[who.length-1]);
	}
}