#include<iostream>
using namespace std;
int d, i, ans = 0;
bool b[1<<20];
void dfs(int x){
    if(x >= (1 << (d-1))){
        ans = x;
        return;
    }
    if(b[x]){
        b[x] = false;
        dfs(2*x+1);
    }else{
        b[x] = true;
        dfs(2*x);
    }
}
int main(){
    ios::sync_with_stdio(false);
    cin >> d >> i;
    for(int ii = 0; ii <= (1 << d); ii++)b[ii] = false;
    while(i--)dfs(1);
    cout << ans;
    return 0;
}