import java.util.*;
import java.math.BigDecimal;

public class Main {
    public static void main(String[] args) throws Exception {
        // Your code here!
        Scanner sc = new Scanner(System.in);
        int dayBefore = sc.nextInt();
        int dayAfter  = sc.nextInt();
        int[] campDay = {23,24,25};
        int answer    = campDay.length; 
         
        if (23 >= dayBefore && 25 <= dayAfter) {
            System.out.println(0);
            System.exit(0);
        }
        
        for (int day : campDay) {
            if (!(day < dayBefore) && !(day > dayAfter)) {
                answer--;
            }
        }
        
        System.out.println(answer);
    }
}