import java.util.*;

public class Main {
  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    String s1 = sc.next();
    String s2 = sc.next();
    int[] holiday = new int[14];
    if(s1.charAt(0) == 'o') holiday[0] = 1;
    for(int i = 1; i < 7; i++) {
      if(s1.charAt(i) == 'o') holiday[i] = holiday[i - 1] + 1;
    }
    for(int i = 0; i < 7; i++) {
      if(s2.charAt(i) == 'o') holiday[i + 7] = holiday[i + 6] + 1;
    }
    int ans = 0;
    for(int i = 0; i < 14; i++) {
      ans = Math.max(ans, holiday[i]);
    }
    System.out.println(ans);
  }
}