mod = 998244353

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

res = 0

f = [[0 for j in range(N+1)] for i in range(K+1)]
for j in range(N+1):
    f[0][j] = 1
t = 1
for i in range(1,K+1):
    t = 2 * t % mod
    f[i][0] = 1
    for j in range(1,N+1):
        f[i][j] = t * f[i][j-1] + f[i-1][j]
        f[i][j] %= mod

def calc_dp(A):
    dp = [[0 for j in range(K+1)] for i in range(N)]
    t = 1
    for j in range(K+1):
        dp[0][j] = t
        t = t * 2 * A[0] % mod
    for i in range(1,N):
        dp[i] = [dp[i-1][j] for j in range(K+1)]
        for j in range(1,K+1):
            dp[i][j] += dp[i][j-1]
            dp[i][j] %= mod
        t0,t1 = 1,1
        for j in range(K+1):
            dp[i][j] = t0 * (f[j][i]*t1+dp[i][j]) % mod
            t0 = 2 * t0 % mod
            t1 = A[i] * t1 % mod
    return dp

dp = calc_dp(A)

c = pow(2,K,mod)
for i in range(1,N):
    rest_way = f[K-1][N-i-1]
    tmp = ((pow(A[i],K,mod) * (c * f[K][i-1] % mod))%mod + dp[i-1][K]) * c % mod
    res += tmp * rest_way % mod
    res %= mod

dp = calc_dp(A[::-1])

for i in range(1,N-1):
    rest_way = c * (c *  f[K][N-2-i] % mod) % mod
    tmp = sum(dp[i-1][k] for k in range(K)) % mod
    res += tmp * rest_way % mod
    res %= mod

i4 = pow(4,mod-2,mod)
res *= pow(i4,K,mod)
print(res % mod)