#include <iostream>
#include <string>
#include <algorithm>
using namespace std;
int main(void){
    int a,b,ans;
    cin>>a>>b;
    for(int i=a;i<b+1;i++){
        if(i==23 || i==24 || i==25){
            ans++;
        }
    }
    cout<<3-ans<<endl;
    
    
}