#include <bits/stdc++.h>
using namespace std;
const double EPS = 0.000001;
int main(){
  int A, B;
  cin >> A >> B;
  int t = A * 3600 + B * 60;
  double t2 = (double) 3600 * 12 / 11;
  double t3 = 0;
  while (t3 + EPS < t){
    t3 += t2;
  }
  cout << (int) (t3 + EPS) - t << endl;
}