## hhttps://yukicoder.me/problems/no/1299

MOD = 998244353

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

    base_average = 0
    for a in A:
        base_average += a
        base_average %= MOD
    base_average *= pow(N, MOD - 2, MOD)
    base_average %= MOD

    answer = pow(2, K, MOD) * base_average
    answer %= MOD
    answer *= N
    answer %= MOD
    print(answer)





if __name__ == '__main__':
    main()