#include <iostream>
using namespace std;
int main(){
  int a,b;cin>>a>>b;a%=12;
  double radA = (60*a+b)%720;
  double radB = 12*b;
  //cout << radA << " " << radB << endl;
  //if(radA > radB)
  double dist = radA-radB;
  if(dist < 0)dist += 720;
  //cout << dist << endl;
  cout << (int)(60*dist/11) << endl;
}