#include <bits/stdc++.h>
using namespace std;
#include <atcoder/all>
using namespace atcoder;
using ll = long long;
using vll = vector<ll>;
using vvll = vector<vll>;
using vvvll = vector<vvll>;
using vvvvll = vector<vvvll>;
using vvvvvll = vector<vvvvll>;
using vvvvvvll = vector<vvvvvll>;
using vb = vector<bool>;
using vvb = vector<vb>;
using vvvb = vector<vvb>;
using vvvvb = vector<vvvb>;
using vd = vector<double>;
using vvd = vector<vd>;
using vvvd = vector<vvd>;
using vvvvd = vector<vvvd>;
using vvvvvd = vector<vvvvd>;
#define all(A) A.begin(),A.end()
#define ALL(A) A.begin(),A.end()
#define rep(i, n) for (ll i = 0; i < (ll) (n); i++)
using pqr = priority_queue<pair<ll, ll>, vector<pair<ll, ll>>, greater<pair<ll, ll>>>;


template<class T>
bool chmax(T& p, T q, bool C = 1) {
    if (C == 0 && p == q) {
        return 1;
    }
    if (p < q) {
        p = q;
        return 1;
    }
    else {
        return 0;
    }
}

template<class T>
bool chmin(T& p, T q, bool C = 1) {
    if (C == 0 && p == q) {
        return 1;
    }
    if (p > q) {
        p = q;
        return 1;
    }
    else {
        return 0;
    }
}

ll gcd(ll(a), ll(b)) {
    if (a == 0)return b;
    if (b == 0)return a;
    ll c = a;
    while (a % b != 0) {
        c = a % b;
        a = b;
        b = c;
    }
    return b;
}
ll sqrtz(ll N) {
    ll L = 0;
    ll R = sqrt(N) + 10000;
    while (abs(R - L) > 1) {
        ll mid = (R + L) / 2;
        if (mid * mid <= N)L = mid;
        else R = mid;
    }
    return L;

}

/*
using mint = modint998244353;
//using Mint = modint;
vector<mint> fact, factinv, inv;
const ll mod = 998244353;
void prenCkModp(ll n) {
    fact.resize(n + 5);
    factinv.resize(n + 5);
    inv.resize(n + 5);
    fact[0] = fact[1] = 1;
    factinv[0] = factinv[1] = 1;
    inv[1] = 1;
    for (ll i = 2; i < n + 5; i++) {
        fact[i] = (fact[i - 1] * i);
        inv[i] = mod - (inv[mod % i] * (mod / i));
        factinv[i] = (factinv[i - 1] * inv[i]);
    }

}

mint nCk(ll n, ll k) {
    if (n < k || k < 0) return 0;
    return fact[n] * (factinv[k] * factinv[n - k]);
}
*/

template<class T>
vector<vector<T>> mul(vector<vector<T>> A, vector<vector<T>> B) {
    ll N = A.size();
    vector<vector<T>> res(N, vector<T>(N, 0));
    rep(i, N)rep(j, N)rep(k, N) {
        res[i][j] += A[i][k] * B[k][j];
    }
    return res;
}


struct rollinghash {
    const ll base = 9973;
    const vector<ll> MoD = { 999999937, 1000000007 };
    string S;
    vector<ll> hash[2], power[2];
    rollinghash(const string& cs) { init(cs); }

    ll Shash(string T, ll iter) {
        ll n = T.size();
        ll reshash = 0;
        ll respow = 1;
        rep(i, n) {
            reshash = (reshash * base + T[i]) % MoD[iter];
        }
        return reshash;
    }

    void init(const string& cs) {
        S = cs;
        ll n = S.size();
        rep(iter, MoD.size()) {
            hash[iter].assign(n + 1, 0);
            power[iter].assign(n + 1, 1);
            rep(i, n) {
                hash[iter][i + 1] = (hash[iter][i] * base + S[i]) % MoD[iter];
                power[iter][i + 1] = power[iter][i] * base % MoD[iter];
            }
        }
    }
    ll get(int l, int r, int id = 0) const {
        return ((hash[id][r] - (hash[id][l] * power[id][r - l]) % MoD[id]) + MoD[id]) % MoD[id];
    }
    ll getLCP(int a, int b) const {
        int len = min((int)S.size() - a, (int)S.size() - b);
        int low = -1, high = len + 1;
        while (high - low > 1) {
            int mid = (low + high) / 2;
            if (get(a, a + mid, 0) != get(b, b + mid, 0)) high = mid;
            else if (get(a, a + mid, 1) != get(b, b + mid, 1)) high = mid;
            else low = mid;
        }
        return low;
    }
};

ll op(ll a, ll b) {
    return a + b;
}
ll e() {
    return 0;
}

using mint=modint998244353;

int main() {

    ll N,L;
    cin>>N>>L;
    mint an=2;
    //cout<<(N+L-1)/L<<endl;
    ll d=(N+L-1)/L;
    an=mint(2).pow(d);
    an--;
    cout<<an.val()<<endl;
}