#include <bits/stdc++.h>
using namespace std;
const double PI = acos(-1);
const double eps = 1e-9;
const int inf = 2000000000;
const long long infLL = 9000000000000000000;
inline bool checkBit(long long n, int i) { return n & (1LL << i); }
inline long long setBit(long long n, int i) { return n | (1LL << i); }
inline long long resetBit(long long n, int i) { return n & (~(1LL << i)); }
inline void normal(long long &a) {
  a %= 1000000007;
  (a < 0) && (a += 1000000007);
}
inline long long modMul(long long a, long long b) {
  a %= 1000000007;
  b %= 1000000007;
  normal(a);
  normal(b);
  return (a * b) % 1000000007;
}
inline long long modAdd(long long a, long long b) {
  a %= 1000000007;
  b %= 1000000007;
  normal(a);
  normal(b);
  return (a + b) % 1000000007;
}
inline long long modSub(long long a, long long b) {
  a %= 1000000007;
  b %= 1000000007;
  normal(a);
  normal(b);
  a -= b;
  normal(a);
  return a;
}
inline long long modPow(long long b, long long p) {
  long long r = 1LL;
  while (p) {
    if (p & 1) r = modMul(r, b);
    b = modMul(b, b);
    p >>= 1;
  }
  return r;
}
inline long long modInverse(long long a) { return modPow(a, 1000000007 - 2); }
inline long long modDiv(long long a, long long b) {
  return modMul(a, modInverse(b));
}
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  ;
  long long p[52];
  p[0] = 1;
  for (int i = 1; i < 52; ++i) {
    p[i] = (1LL << i);
    p[i] += p[i - 1];
  }
  long long n, h;
  cin >> h >> n;
  long long ans = 0LL;
  int lev = 0;
  int cnt = 0;
  while (lev < h) {
    if (cnt % 2 == 0) {
      if (n > (1LL << (h - lev - 1))) {
        ans += p[h - lev - 1];
        n -= (1LL << (h - lev - 1));
        cnt++;
      }
    } else {
      if (n <= (1LL << (h - lev - 1))) {
        ans += p[h - lev - 1];
        cnt++;
      } else {
        n -= (1LL << (h - lev - 1));
      }
    }
    ans++;
    lev++;
    cnt++;
  }
  cout << ans << '\n';
  return 0;
}
