#include <bits/stdc++.h>

using namespace std;
using ll = long long;
using i128 = __int128;
using pll = pair<ll, ll>;
using vll = vector<ll>;
template <class T>
using max_heap = priority_queue<T>;
template <class T>
using min_heap = priority_queue<T, vector<T>, greater<>>;

constexpr ll INF = (1LL << 60);
ll ALPHABET_N = 26;
#define rep(i, n) for (ll i = (ll)0; i < (ll)n; i++)
#define rep_(i, k, n) for (ll i = (ll)k; i < (ll)n; i++)
#define rrep(i, n) for (ll i = (ll)(n) - 1; i >= 0; i--)
#define all(a) a.begin(), a.end()

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;
}

#include <atcoder/all>
using namespace atcoder;
using mint = modint998244353;

int main()
{
    ios::sync_with_stdio(false);
    cin.tie(0);
    ll n, m;
    cin >> n >> m;
    auto large_comb = [](mint n, mint r, ll loop) -> mint
    {
        mint a = 1;
        mint b = 1;
        rep(_, loop)
        {
            a *= (n - _);
            b *= (r - _);
        }
        return a / b;
    };
    if (n < 30)
    {
        ll lim = 1LL << (n - 1);
        if (lim < m)
        {
            mint a = mint(2).pow(n) - 1;
            cout << large_comb(a, m, m).val() << endl;
            return 0;
        }
    }
    mint a = mint(2).pow(n) - 1;
    mint b = mint(2).pow(n - 1);
    mint ans = large_comb(a, m, m) - large_comb(b, m, m) * (mint(2).pow(n) - 1);
    cout << ans.val() << endl;
    return 0;
}