#include<bits/stdc++.h>
#define rep(i,a,b) for(int i=int(a);i<int(b);++i)
using namespace std;
typedef long long ll;
int INF = (1LL << 30) - 1;
int MOD = 1e9+7;
main(){
    int A,B;
    cin >> A >> B;
    int cnt = 3;
    rep(i,23,26){
        if(i >= A && i <= B)cnt--;
    }
    cout << cnt << endl;
}