#include <iostream>
#include <algorithm>
#include <cmath>
#include <vector>
#include <string>
#include <map>
#include <queue>
#include <set>
#include <stack>
#include <iomanip>
using ll = long long;
using uint = unsigned int;
using graph = std::vector<std::vector<ll>>;
using wGraph = std::vector<std::vector<std::pair<ll,ll>>>;
#define rep(i,n) for (int i=0; i < int(n); i++)

using namespace std;
ll MOD7 = 1000000007;
ll MOD9 = 1000000009;
vector<ll> InputVec(ll N){
    vector<ll> A(N);
    for (int i = 0; i < N; ++i) {
        cin >> A[i];
    }
    return A;
}
void OutputVec(vector<ll> A){
    for (int i = 0; i < A.size(); ++i) {
        cout << A[i] << ",";
    }
    cout << endl;
}
vector<vector<ll>> InputVec2d(ll H,ll W){
    vector<vector<ll>> A(H);
    for (int yi = 0; yi < H; ++yi) {
        A[yi] = vector<ll>(W);
    }
    for (int yi = 0; yi < H; ++yi) {
        for (int xi = 0; xi < W; ++xi) {
            cin >> A[yi][xi];
        }
    }
    return A;
}
vector<vector<char>> InputVec2dStr(ll H,ll W){
    vector<vector<char>> A(H);
    for (int yi = 0; yi < H; ++yi) {
        A[yi] = vector<char>(W);
    }
    for (int yi = 0; yi < H; ++yi) {
        string S;
        cin >> S;
        for (int xi = 0; xi < W; ++xi) {
            A[yi][xi] = S[xi];
        }
    }
    return A;
}
void OutputVec2d(vector<vector<ll>> A){
    for (int yi = 0; yi < A.size(); ++yi) {
        for (int xi = 0; xi < A[yi].size(); ++xi) {
            cout << A[yi][xi] << ",";
        }
        cout << endl;
    }
}
graph InputGraph(ll N,ll M){
    graph G(N);
    for (int i = 0; i < M; ++i) {
        ll a,b;
        cin >> a >> b;
        a--;b--;
        G[a].push_back(b);
        G[b].push_back(a);
    }
    return G;
}
graph InputDGraph(ll N,ll M){
    graph G(N);
    for (int i = 0; i < M; ++i) {
        ll a,b;
        cin >> a >> b;
        a--;b--;
        G[a].push_back(b);
    }
    return G;
}
void OutputGraph(graph G){
    for (int i = 0; i < G.size(); ++i) {
        cout << i << ":";
        for (int j = 0; j < G[i].size(); ++j) {
            cout << G[i][j]<< ",";
        }
        cout << endl;
    }
}
void OutputAnswerBool(bool b,bool isUpperCase = false){
    if(b){
        if(isUpperCase){
            cout << "YES" << endl;
        }else{
            cout << "Yes" << endl;
        }
    }else{
        if(isUpperCase){
            cout << "NO" << endl;
        }else{
            cout << "No" << endl;
        }
    }
}

vector<ll> c;
vector<ll> p;
void init(){
    c = vector<ll>(55);
    p = vector<ll>(55);
    c[1] = 5;
    p[1] = 3;
    for (int i = 2; i < 55; ++i) {
        c[i] = c[i-1] * 2 + 3;
        p[i] = p[i-1] * 2 + 1;
    }
}
ll solve(ll x,ll pos){
    if(x == 1){
        return min(3ll,pos);
    }
    if(pos == 0){
        return 0;
    }
    pos--;
    if(pos < c[x-1]){
        return solve(x-1,pos);
    }
    if(pos == c[x-1]){
        return p[x-1]+1;
    }
    pos--;
    pos-=c[x-1];
    return p[x-1] + solve(x-1,pos)+1;

}
int main() {
    init();
    ll N,X;
    cin >> N >> X;
    X--;
    for (int i = 0; i < c[3]; ++i) {
        //cout << solve(3,i) << ",";
    }
    cout << solve(N,X) << endl;
}


Measured memory_bytes: 256