#include <bits/stdc++.h>
#define rep(i,n) for (int i=0; i < (n); i++)
using namespace std;
using ll = long long;


ll mod = 998244353;

long long modpow(long long a, long long n, long long mod) {
    long long res = 1;
    while (n > 0) {
        if (n & 1) res = res * a % mod;
        a = a * a % mod;
        n >>= 1;
    }
    return res;
}


int main(){
    ios::sync_with_stdio(false);
    ll N,L; cin>>N>>L;
    if(N<=L){
        cout << 1 << endl;
        return 0;
    }
    
    N = N/L + 1;
    cerr << N << endl;

    ll ans=2;
    ans = modpow(ans, N, mod);
    // cerr << ans << endl;
    // ans = (ans + MOD)%MOD;
    // cerr << ans << endl;
    cout << ans - 1 << endl;

}