#include<bits/stdc++.h>
using namespace std;
using Int = long long;
template<typename T1,typename T2> inline void chmin(T1 &a,T2 b){if(a>b) a=b;}
template<typename T1,typename T2> inline void chmax(T1 &a,T2 b){if(a<b) a=b;}

//INSERT ABOVE HERE
signed main(){
  int a,b;
  cin>>a>>b;
  chmax(a,23);
  chmin(b,25);
  cout<<3-max(0,b-a+1)<<endl;
  return 0;
}