#include <iostream>

using namespace std;

using ll = long long;
#define rep(i, n) for (ll i = 0; i < ll(n); i++)

const int MAX = 220000;
const int MOD = 998244353;

ll fac[MAX], finv[MAX], inv[MAX];

// テーブルを作る前処理
void COMinit() {
    fac[0] = fac[1] = 1;
    finv[0] = finv[1] = 1;
    inv[1] = 1;
    for (int i = 2; i < MAX; i++){
        fac[i] = fac[i - 1] * i % MOD;
        inv[i] = MOD - inv[MOD%i] * (MOD / i) % MOD;
        finv[i] = finv[i - 1] * inv[i] % MOD;
    }
}

// 二項係数計算
ll COM(int n, int k){
    if (n < k) return 0;
    if (n < 0 || k < 0) return 0;
    return fac[n] * (finv[k] * finv[n - k] % MOD) % MOD;
}

//剰余考慮版繰り返し二乗法(x^n % mod2 を計算)
ll mpow(ll x, ll n){
    ll ret = 1;
    while(n > 0){
        if(n & 1) ret = ret * x % MOD;
        x = x * x % MOD;
        n >>= 1;
    }

    return ret;
}


int main(){
    ll N,K; cin >> N >> K;

    COMinit();

    ll ans = 0;
    rep(i,N){
        ans += mpow(i,K) * COM(N-1, i) % MOD;
        ans %= MOD;
    }

    cout << ans << endl;

}