#include <iostream>
#include <map>
#include <set>
#include <queue>
#include <cmath>
#include <vector>
#include <string>
#include <algorithm>
#include <functional>
using namespace std;
#pragma warning (disable: 4996)

long long modpow(long long a, long long b, long long m) {
	long long p = 1, q = a;
	for (int i = 0; i < 63; i++) {
		if ((b / (1LL << i)) % 2LL == 1) { p *= q; p %= m; }
		q *= q; q %= m;
	}
	return p;
}

long long mod = 998244353;
long long N, K;

int main() {
	cin >> N >> K;
	long long x = (N + K - 1) / K;
	cout << (modpow(2, x, mod) + mod - 1) % mod << endl;
	return 0;
}