#include <bits/stdc++.h>
using namespace std;
using i64 = long long;
using ll = long long;
#define SZ(v) (ll)((v).size())
#define pb emplace_back
#define AI(i) begin(i), end(i)
#define X first
#define Y second
template<class T> bool chmin(T &a, T b) { return b < a && (a = b, true); }
template<class T> bool chmax(T &a, T b) { return a < b && (a = b, true); }
#ifdef KEV
#define DE(args...) kout("[ " + string(#args) + " ] = ", args)
void kout() { cerr << endl; }
template<class T, class ...U> void kout(T a, U ...b) { cerr << a << ' ', kout(b...); }
template<class T> void debug(T l, T r) { while (l != r) cerr << *l << " \n"[next(l)==r], ++l; }
#else
#define DE(...) 0
#define debug(...) 0
#endif
int main() {
  cin.tie(nullptr)->sync_with_stdio(false);

  int n, m;
  cin >> n >> m;

  cout << 2 * max({(n + 3) / 4, (m + 3) / 4, (n + m + 6) / 7}) - 1 << '\n';
  return 0;
}