## https://yukicoder.me/problems/no/1400

MOD = 998244353


class CombinationCalculator:
    """
    modを考慮したPermutation, Combinationを計算するためのクラス
    """    
    def __init__(self, size, mod):
        self.mod = mod
        self.factorial = [0] * (size + 1)
        self.factorial[0] = 1
        for i in range(1, size + 1):
            self.factorial[i] = (i * self.factorial[i - 1]) % self.mod
        
        self.inv_factorial = [0] * (size + 1)
        self.inv_factorial[size] = pow(self.factorial[size], self.mod - 2, self.mod)

        for i in reversed(range(size)):
            self.inv_factorial[i] = ((i + 1) * self.inv_factorial[i + 1]) % self.mod

    def calc_combination(self, n, r):
        if n < 0 or n < r or r < 0:
            return 0

        if r == 0 or n == r:
            return 1
        
        ans = self.inv_factorial[n - r] * self.inv_factorial[r]
        ans %= self.mod
        ans *= self.factorial[n]
        ans %= self.mod
        return ans
    
    def calc_permutation(self, n, r):
        if n < 0 or n < r:
            return 0

        ans = self.inv_factorial[n - r]
        ans *= self.factorial[n]
        ans %= self.mod
        return ans
        

def main():
    N, K = map(int, input().split())

    # nの差で主客転倒
    combi = CombinationCalculator(N, MOD)
    answer = 0
    for n in range(1, N):
        e = 2 * N - 2 * n
        e %= MOD

        x = combi.factorial[N - 1]
        ans0 = (e * x) % MOD
        ans1 = pow(n, K, MOD)
        ans = (ans0 * ans1) % MOD

        answer += ans
        answer %=MOD
    print(answer)





    



if __name__ == "__main__":
    main()