S=input()
N=len(S)
c=S.count("?")
'''
主客転倒
i<j<kが0,1,0になる
?の数：cnt 2^(c-cnt)
'''
mod=998244353
ans=0
A=[0 for i in range(N)]
inv2=pow(2,mod-2,mod)
for i in range(N):
    if S[i]=="0":
        A[i]=1
    elif S[i]=="?":
        A[i]=inv2
    else:
        A[i]=0

X=[0 for i in range(N+1)]
Y=[0 for i in range(N+1)]
for i in range(N):
    X[i+1]=X[i]+A[i]
for i in range(N-1,-1,-1):
    Y[i]=Y[i+1]+A[i]
for i in range(N):
    if S[i]=="1":
        ans+=X[i]*Y[i+1]
        ans%=mod
    elif S[i]=="?":
        ans+=X[i]*Y[i+1]*inv2
        ans%=mod
ans*=pow(2,c,mod)
ans%=mod
print(ans)