#include <bits/stdc++.h>
using namespace std;

int main()
{
    int N, M;
    cin >> N >> M;
    long long ans = 0;
    int i = 0;
    int last_add = M;
    for (i = 0; i < N && last_add != 1; ++i)
    {
        ans += M;
        last_add = M;
        M = (M + 1) / 2;
    }
    if(i == N && last_add != 1)
    {
        cout << ((1<<N)-1) << endl;
        return 0;
    }
    ans += N - i;
    cout << ans << endl;
}