#pragma region Macros

// #pragma GCC target("avx,avx2,fma")
// #pragma GCC optimize("O3,unroll-loops")

#include <bits/extc++.h>
// #include <atcoder/all>
// using namespace atcoder;
using namespace std;
using namespace __gnu_pbds;

// #include <boost/multiprecision/cpp_dec_float.hpp>
// #include <boost/multiprecision/cpp_int.hpp>
// namespace mp = boost::multiprecision;
// using Bint = mp::cpp_int;
// using Bdouble = mp::number<mp::cpp_dec_float<128>>;

#define TO_STRING(var) # var
#define pb emplace_back
#define int ll
#define endl '\n'
#define sqrt __builtin_sqrt

using ll = long long;
using ld = long double;
const ld PI = acos(-1);
const ld EPS = 1e-10;
const int INF = 1 << 30;
const ll INFL = 1LL << 61;
// const int MOD = 998244353;
const int MOD = 1000000007;

__attribute__((constructor))
void constructor() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    // ifstream in("input.txt");
    // cin.rdbuf(in.rdbuf());
    cout << fixed << setprecision(12);
}

class UnionFind {
public:

	UnionFind() = default;

    UnionFind(int N) : par(N), sz(N, 1) {
        iota(par.begin(), par.end(), 0);
    }

	int root(int x) {
		if (par[x] == x) return x;
		return (par[x] = root(par[x]));
	}

	bool unite(int x, int y) {
		int rx = root(x);
		int ry = root(y);

        if (rx == ry) return false;
		if (sz[rx] < sz[ry]) swap(rx, ry);

		sz[rx] += sz[ry];
		par[ry] = rx;

        return true;
	}

	bool issame(int x, int y) { return (root(x) == root(y)); }
	int size(int x) { return sz[root(x)]; }

    vector<vector<int>> groups(int N) {
        vector<vector<int>> G(N);
        for (int x = 0; x < N; x++) {
            G[root(x)].push_back(x);
        }
		G.erase(
            remove_if(G.begin(), G.end(),
                [&](const vector<int>& V) { return V.empty(); }),
                    G.end());
        return G;
    }

private:
	vector<int> par;
	vector<int> sz;
};

template<int mod> class Modint{
public:
    int val = 0;
    Modint(int x = 0) { while (x < 0) x += mod; val = x % mod; }
    Modint(const Modint &r) { val = r.val; }

    Modint operator -() { return Modint(-val); }
    Modint operator +(const Modint &r) { return Modint(*this) += r; }
    Modint operator +(const int &q) { Modint r(q); return Modint(*this) += r; }
    Modint operator -(const Modint &r) { return Modint(*this) -= r; }
    Modint operator -(const int &q) { Modint r(q); return Modint(*this) -= r; }
    Modint operator *(const Modint &r) { return Modint(*this) *= r; }
    Modint operator *(const int &q) { Modint r(q); return Modint(*this) *= r; }
    Modint operator /(const Modint &r) { return Modint(*this) /= r; }
    Modint operator /(const int &q) { Modint r(q); return Modint(*this) /= r; }
    Modint& operator ++() { val = (val + 1) % mod; return *this; }
    Modint& operator --() { val = (val - 1 + mod) % mod; return *this; }

    Modint &operator +=(const Modint &r) {
        val += r.val; if (val >= mod) val -= mod;
        return *this;
    }
    Modint &operator +=(const int &q) {
        Modint r(q); val += r.val; if (val >= mod) val -= mod;
        return *this;
    }
    Modint &operator -=(const Modint &r) {
        if (val < r.val) val += mod; val -= r.val;
        return *this;
    }
    Modint &operator -=(const int &q) {
        Modint r(q);  if (val < r.val) val += mod; val -= r.val;
        return *this;
    }
    Modint &operator *=(const Modint &r) {
        val = val * r.val % mod;
        return *this;
    }
    Modint &operator *=(const int &q) {
        Modint r(q); val = val * r.val % mod;
        return *this;
    }
    Modint &operator /=(const Modint &r) {
        int a = r.val, b = mod, u = 1, v = 0;
        while (b) {int t = a / b; a -= t * b; swap(a, b); u -= t * v; swap(u, v);}
        val = val * u % mod; if (val < 0) val += mod;
        return *this;
    }
    Modint &operator /=(const int &q) {
        Modint r(q); int a = r.val, b = mod, u = 1, v = 0;
        while (b) {int t = a / b; a -= t * b; swap(a, b); u -= t * v; swap(u, v);}
        val = val * u % mod; if (val < 0) val += mod;
        return *this;
    }

    bool operator ==(const Modint& r) { return this -> val == r.val; }
    bool operator <(const Modint& r) { return this -> val < r.val; }
    bool operator !=(const Modint& r) { return this -> val != r.val; }
};

using mint = Modint<MOD>;
// using mint = modint<MOD>;

istream &operator >>(istream &is, mint& x) {
    int t; is >> t;
    x = t;
    return (is);
}
ostream &operator <<(ostream &os, const mint& x) {
    return os << x.val;
}

mint modpow(const mint &x, int n) {
    if (n == 0) return 1;
    mint t = modpow(x, n / 2);
    t = t * t;
    if (n & 1) t = t * x;
    return t;
}

int modpow(__int128_t x, int n, int mod) {
    __int128_t ret = 1;
    while (n > 0) {
        if (n % 2 == 1) ret = ret * x % mod;
        x = x * x % mod;
        n /= 2;
    }
    return ret;
}
int POW(int x, int n) {
    __int128_t ret = 1;
    if (n < 0) { cout << "error" << endl; return 0; }
    else if (x == 1 or n == 0) ret = 1;
    else if (x == -1 && n % 2 == 0) ret = 1; 
    else if (x == -1) ret = -1; 
    else if (n % 2 == 0) ret = POW(x * x, n / 2);
    else ret = x * POW(x, n - 1);

    if (ret > 8e18) ret = 0; // llに収まらない範囲は0埋め
    return ret;
}
int floor(int x, int y) { return (x > 0 ? x / y : (x - y + 1) / y); }
int ceil(int x, int y) { return (x > 0 ? (x + y - 1) / y : x / y); }
int per(int x, int y) {
    if (y == 0) {
        cout << "error" << endl;
        return INFL;
    }
    if (x >= 0 && y > 0) return x / y;
    if (x >= 0 && y < 0) return x / y - (x % y < 0);
    if (x < 0 && y < 0) return x / y + (x % y < 0);
    if (x < 0 && y > 0) return x / y - (x % y < 0);
}
int mod(int x, int y) {
    if (y == 0) {
        cout << "error" << endl;
        return INFL;
    }
    if (x >= 0 && y > 0) return x % y;
    if (x >= 0 && y < 0) return x % y;
    if (x < 0 && y < 0) {
        __int128_t ret = x % y;
        ret += (__int128_t)abs(y) * INFL;
        ret %= abs(y);
        return ret;
    }
    if (x < 0 && y > 0) {
        __int128_t ret = x % y;
        ret += (__int128_t)abs(y) * INFL;
        ret %= abs(y);
        return ret;
    }
}

template <class T> bool chmax(T &a, const T& b) {
    if (a < b) { a = b; return true; }
    return false;
}
template <class T> bool chmin(T &a, const T& b) {
    if (a > b) { a = b; return true; }
    return false;
}

int countl_zero(int N) { return __builtin_clzll(N); }
int countl_one(int N) {
    int ret = 0; while (N % 2) { N /= 2; ret++; }
    return ret;
}
int countr_zero(int N) { return __builtin_ctzll(N); }
int countr_one(int N) {
    int ret = 0, k = 63 - __builtin_clzll(N);
    while (k != -1 && (N & (1LL << k))) { k--; ret++; }
    return ret;
}
int popcount(int N) { return __builtin_popcountll(N); }
int unpopcount(int N) { return 64 - __builtin_clzll(N) - __builtin_popcountll(N); }

int top_bit(int N) { return 63 - __builtin_clzll(N);} // 2^kの位
int bot_bit(int N) { return __builtin_ctz(N);} // 2^kの位
int MSB(int N) { return 1 << (63 - __builtin_clzll(N)); } // mask
int LSB(int N) { return (N & -N); } // mask

int bit_width(int N) { return 64 - __builtin_clzll(N); } // 桁数
int ceil_log2(int N) { return 63 - __builtin_clzll(N); }
int bit_floor(int N) { return 1 << (63 - __builtin_clzll(N)); }
int floor_log2(int N) { return 64 - __builtin_clzll(N-1); }
int bit_ceil(int N) { return 1 << (64 - __builtin_clzll(N-1)) - (N==1); }

vector<mint> fac, finv, Inv;
void COMinit(int N) {
    fac.resize(N + 1);
    finv.resize(N + 1);
    Inv.resize(N + 1);
    fac[0] = fac[1] = 1;
    finv[0] = finv[1] = 1;
    Inv[1] = 1;
    for (int i = 2; i <= N; i++) {
        fac[i] = fac[i-1] * mint(i);
        Inv[i] = -Inv[MOD % i] * mint(MOD / i);
        finv[i] = finv[i - 1] * Inv[i];
    }
}

mint COM(int N, int K) {
    if (N < K) return 0;
    if (N < 0 || K < 0) return 0;
    return fac[N] * finv[K] * finv[N - K];
}

#pragma endregion

signed main() {
    int N, M;
    cin >> N >> M;
    int ans = M;
    int cnt = 1;
    while (M != 1 && cnt + 1 < N) {
        ans += ceil(M, 2);
        M = ceil(M, 2);
        cnt++;
    }
    cout << ans + (N - cnt) << endl;
}