#include <bits/stdc++.h>
#define rep(i,n) for(int i = 0; i < (n); ++i)
#define srep(i,s,t) for(int i = s; i < t; ++i)
#define drep(i,n) for(int i = (n)-1; i >= 0; --i)
using namespace std;
typedef long long int ll;
typedef pair<int,int> P;
#define yn {puts("Yes");}else{puts("No");}
#define MAX_N 200005

ll mod_pow(ll x, ll n, ll mod){ // x ^ n % mod
    ll res = 1;
    while(n > 0){
        if (n & 1) res = res * x % mod;
        x = x * x % mod;
        n >>= 1;
    }
    return res;
}

int main() {
    ll MOD = 998244353;
    ll n, l;
    cin >> n >> l;
    n = (n-1)/l+1;
    ll ans = mod_pow(2,n,MOD) - 1;
    cout << ans << endl;
    return 0;
}