#include <bits/stdc++.h>

using namespace std;

#ifdef LOCAL
#include <debug.hpp>
#else
#define debug(...) void()
#endif

int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  int h, m;
  cin >> h >> m;
  if (h >= 12) h -= 12;
  int lon = h * 3600 + m * 60;
  int sho = m * 60 * 12;
  int dist = lon - sho;
  if (dist < 0) dist += 3600 * 12;
  cout << dist / 11 << '\n';
  return 0;
}