s=[*input()]
n=len(s)
c=s.count("?")
dp=[[0]*4 for _ in range(n+1)]
dp[0][0]=1
for i in range(1,n+1):
    if s[i-1]=="0" or s[i-1]=="?":
        dp[i][1]+=dp[i-1][0]
        dp[i][3]+=dp[i-1][2]
    if s[i-1]=="1" or s[i-1]=="?":
        dp[i][2]+=dp[i-1][1]
    for j in range(4):
        dp[i][j]+=dp[i-1][j]*(1+(s[i-1]=="?"))
        dp[i][j]%=998244353
print(dp[-1][-1])