#include <iostream>

constexpr int mod = 998244353;

int solve(long long int n){
    if(n == 0) return 1;
    const int t = solve(n / 2);
    const int s = static_cast<long long int>(t) * t % mod;
    if(n % 2 == 0) return s;
    return (2L * s) % mod;
}

int main(void){
    long long int n, L; std::cin >> n >> L;
    const long long int r = (n % L == 0) ? n / L : n / L + 1;
    std::cout << solve(r) - 1 << '\n';
    return 0;
}