MOD = 998244353
N,K = list(map(int,input().split()))
A = list(map(int,input().split()))

def less_than(n):
	ret = 1
	for i in A:
	 if(i <= n):continue
	 ret *= n * pow(i,-1,MOD)
	 ret %= MOD
	return ret

ans = (less_than(K) - less_than(K-1)) % MOD
print(ans)