#include <bits/stdc++.h>

using namespace std;
typedef long long ll;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;
typedef tuple<int, int, int> tii;
typedef tuple<ll, ll, ll> tll;
typedef long double ld;
typedef vector<int> vi;
typedef vector<ll> vl;
#define mp make_pair
#define pb push_back
#define eb emplace_back
#define nl "\n"
#define all(v) v.begin(),v.end()
#define rep(i, a, b) for(int i = a; i < (b); ++i)
#define sz(x) (int)(x).size()

mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count()); 
const int maxn = 1e6 + 5;
const ll mod = 998244353;

ll fpow(int b, int p) {
    ll res = 1;
    b %= mod;
    while (p) {
        if (p & 1) {
            res = (ll) res * b % mod;
        }
        b = (ll) b * b % mod;
        p >>= 1;
    }
    return res;
}
ll fac[maxn], ifac[maxn]; 

ll inv(ll a) {
	return fpow(a, mod - 2);
}

ll ncr(ll a, ll b){
	if (b > a) return 0;
	return fac[a] * ifac[b] % mod * ifac[a-b] % mod;
}

void initfac(){
	fac[0] = 1;
	for (int i = 1; i < maxn; i++) fac[i] = fac[i-1] * i % mod;
	ifac[maxn - 1] = inv(fac[maxn - 1]);
	for (int i = maxn - 1; i >= 1; i--) ifac[i - 1] = ifac[i] * i % mod;
}


ll n, m, q, k, t, a, b, c;

int main(){
	ios::sync_with_stdio(0);
	cin.tie(0);
	initfac();
	cin >> n >> k;
	if (k % 2) {
		cout << fpow(n, k) * inv(2) % mod * (n + 1) % mod;
	} else {
		ll ans = fpow(n, k) * (n + 1) % mod;
		ll nck = ncr(k, k / 2);
		k = k / 2;
		for (ll i = 1; i <= n - 1; i++) {
			ans = (ans - nck * fpow(i * (n - i), k)) % mod;
		}
		ans = (ans + mod) * inv(2) % mod;
		cout << ans;
	}
}