// #define _GLIBCXX_DEBUG
#include<bits/stdc++.h>
using namespace std;

int A,B;

int main(){
  ios::sync_with_stdio(false);
  std::cin.tie(nullptr);
  cout<<fixed<<setprecision(15);

  cin>>A>>B;A%=12;

  double init_A=(double)(360*A)/12 + double(B*360)/(60*12);
  double init_B=(double)(360*B)/60;

  double ato=init_A-init_B;
  if(ato<0)ato+=360;
  if(ato==0){
    cout<<0<<endl; return 0;
  }
  double diff=(double)360/(60*60) - (double)360/(60*60*12);
  double s=ato/diff;
  s=floor((s*1000000)+0.5)/1000000;
  cout<<(int)s<<endl;
}