S=input()
mod=998244353
N=len(S)
DP=[[0,0,0,0] for i in range(N+1)]
DP[0][0]=1
for i in range(N):
  v=1
  if S[i]=='?':
    v=2
  for j in range(4):
    DP[i+1][j]=DP[i][j]*v%mod
  if S[i]=='0' or S[i]=='?':
    DP[i+1][1]=(DP[i+1][1]+DP[i][0])%mod
    DP[i+1][3]=(DP[i+1][3]+DP[i][2])%mod
  if S[i]=='1' or S[i]=='?':
    DP[i+1][2]=(DP[i+1][2]+DP[i][1])%mod
print(DP[N][3])