#include <bits/stdc++.h>
typedef long long ll;
using namespace std;
const int N = 1e6 + 10, mod = 998244353, inv2 = 499122177;

int n, k;
ll fac[N], ifac[N];

ll power(ll a, ll b) {
	ll ans = 1;
	for (;b ;b >>= 1) {
		if (b & 1) ans = ans * a % mod;
		a = a * a % mod;
	}
	return ans;
}

void init(int n = N - 1) {
	fac[0] = 1;
	for (int i = 1; i <= n; i++) fac[i] = fac[i - 1] * i % mod;
	ifac[n] = power(fac[n], mod - 2);
	for (int i = n - 1; ~i; i--) ifac[i] = ifac[i + 1] * (i + 1) % mod;
}

ll C(ll a, ll b) {
	return fac[a] * ifac[b] % mod * ifac[a - b] % mod;
}

int main() {
	cin >> n >> k;
	ll ans = 0;
	init();
	for (int i = 1; i * 2 < n; i++) {
		ans = (ans + power(n, k)) % mod;
		if (k % 2 == 0) ans = (ans + mod - C(k, k / 2) * power(1ll * i * (n - i) % mod, k / 2) % mod) % mod;
	}
	if (n % 2 == 0) {
		ll tmp = power(n / 2, k);
		for (int i = 0; i <= (k - 1) / 2; i++)
			ans = (ans + C(k, i) * tmp % mod) % mod;
	}
	cout << (ans + power(n, k)) % mod << endl;
	return 0;
}