#include <bits/stdc++.h>
#define pb emplace_back
#define fst first
#define scd second
#define mkp make_pair
#define mems(a, x) memset((a), (x), sizeof(a))

using namespace std;
typedef long long ll;
typedef double db;
typedef unsigned long long ull;
typedef long double ldb;
typedef pair<ll, ll> pii;

const int maxn = 1000100;
const ll mod = 998244353;

inline ll qpow(ll b, ll p) {
	ll res = 1;
	while (p) {
		if (p & 1) {
			res = res * b % mod;
		}
		b = b * b % mod;
		p >>= 1;
	}
	return res;
}

ll n, m, f[maxn], pw[maxn], wp[maxn], g[maxn];

void solve() {
	scanf("%lld%lld", &n, &m);
	pw[0] = wp[0] = 1;
	ll inv = qpow(m * m % mod, mod - 2);
	for (int i = 1; i <= n; ++i) {
		pw[i] = pw[i - 1] * m % mod;
		wp[i] = wp[i - 1] * inv % mod;
	}
	for (int i = 1; i <= n; ++i) {
		f[i] = (pw[i] - g[i / 2] * pw[i] % mod + mod) % mod;
		g[i] = (g[i - 1] + wp[i] * f[i]) % mod;
	}
	ll ans = f[n];
	if (n % 2 == 0) {
		ans = (ans + f[n / 2]) % mod;
	}
	printf("%lld\n", (pw[n] + mod - ans) % mod);
}

int main() {
	int T = 1;
	// scanf("%d", &T);
	while (T--) {
		solve();
	}
	return 0;
}