#include <bits/stdc++.h>
using namespace std;
template <class C>
void mini(C& _a4, C _b4) {
  _a4 = min(_a4, _b4);
}
template <class C>
void maxi(C& _a4, C _b4) {
  _a4 = max(_a4, _b4);
}
template <class TH>
void _dbg(const char* sdbg, TH h) {
  cerr << sdbg << '=' << h << endl;
}
template <class TH, class... TA>
void _dbg(const char* sdbg, TH h, TA... a) {
  while (*sdbg != ',') cerr << *sdbg++;
  cerr << '=' << h << ',';
  _dbg(sdbg + 1, a...);
}
template <class T>
ostream& operator<<(ostream& os, vector<T> V) {
  os << "[";
  for (auto& vv : V) os << vv << ",";
  os << "]";
  return os;
}
long long licz(long long n, long long x) {
  if (x * 2 == n) return 3 * x;
  if (x * 2 < n) x = n - x;
  (n, x);
  return 3 * (n - x) + licz(x, 2 * x - n);
}
int32_t main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cout << fixed << setprecision(11);
  if (0) cout << fixed << setprecision(6);
  long long n, x;
  cin >> n >> x;
  cout << licz(n, x) << endl;
}
