#define _USE_MATH_DEFINES
#define _CRT_SECURE_NO_WARNINGS
#include<stdio.h>
#include<string>
#include<iostream>
#include<iostream>
#include<cctype>
#include<cstdio>
#include<vector>
#include<stack>
#include<queue>
#include <algorithm>
#include<math.h>
#include<set>
#include<map>
#include <sstream>
#include<iomanip>
#include <ctype.h>
#include <fstream>
#include <cassert>
#include <bits/stdc++.h>
using namespace std;

//#include<bits/stdc++.h>


	
int main() {

	int a, b;
	cin >> a >> b;
	int t = 3;
	for (int i = a; i <= b; i++)
		if (i >= 23 && i <= 25)t--;
	cout << t << endl;

	return 0;
}