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

int main(){
  double a,b,h,m;
  cin>>a>>b;
  if(a>=12){
    a-=12;
  }
  h=a*30+(b/60)*30;
  if(b==0){
    b+=60;
  }
  m=b*6;
  if(h<m){
    h+=360;
  }
  //cout<<setprecision(5)<<h<<" "<<m<<endl;
  double ans=((h-m)/5.5)*60;
  if(ans>=3600){
    ans-=3600;
  }
  cout<<floor(ans)<<endl;
  return 0;
}