#include <bits/stdc++.h>
using namespace std;
#pragma GCC target("avx")
#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")
typedef long long ll;
typedef pair<ll,ll> prl;
typedef vector<ll> vcl;
typedef map<ll,ll> mapl;
typedef unordered_map<ll,ll> umap;
#define pb push_back
#define all(v) v.begin(), v.end()
#define rep(i,a,b) for(ll i=a;i<=b;i++)
#define repi(i,a,b) for(int i=a;i<=b;i++)
#define repr(i,a,b) for(ll i=a;i>=b;i--)
#define reps(i,v) for(ll i=0;i<v.size();i++)
template<typename T> void chmin(T &a, const T &b) { a = min(a, b); }
template<typename T> void chmax(T &a, const T &b) { a = max(a, b); }
const ll mod = 998244353;

ll powmod(ll px, ll py, ll pmod){
	if(py == 0) return 1;
	if(py % 2 == 0) return powmod((px * px) % pmod, py / 2, pmod);
	else return (px * powmod(px, py - 1, pmod)) % pmod;
} 

int main() {
    // your code goes here
    ll n,l,ans=1;
    cin >> n >> l;
    n = (n-1)/l+1;
    cout << (powmod(2,n,mod)+mod-1)%mod << endl;
    return 0;
}