S,T=input().split()
M=998244353
q=[0]*(len(T)+1)
q[0]=1
for i in range(len(S)):
  for j in reversed(range(len(T))):
    if S[i]==T[j]:
      q[j+1]+=q[j]
      q[j+1]%=M
print(q[len(T)]*pow(2,len(S)-len(T),M)%M)