n,k,*a=map(int,open(0).read().split())
M=998244353
t=1
for i in a:
  if i>=k:
    t*=k*pow(i,M-2,M)
    t%=M
ans=1
for i in a:
  if i>=k-1:
    ans*=(k-1)*pow(i,M-2,M)
    ans%=M
ans=t-ans
print(ans%M)