import itertools
S = list(input())
Q = [0]*len(S)
Z = [0]*len(S)
mod = 998244353
for i,s in enumerate(S):
    if s=='0':
        Z[i]=1
    if s=='?':
        Q[i]=1
ZAC = list(itertools.accumulate(Z))
QAC = list(itertools.accumulate(Q))
ans = 0

def modinv(a):
    return pow(a, mod-2, mod)
div2 = modinv(2)

for i,s in enumerate(S):
    if i==0 or i==len(S)-1:
        continue
    if s=='1' or s=='?':
        leftZ = ZAC[i-1]
        leftQ = QAC[i-1]
        rightZ = ZAC[-1]-ZAC[i]
        rightQ = QAC[-1]-QAC[i]
        left = (pow(2,leftQ,mod)*(leftZ+leftQ*div2))%mod
        right = (pow(2,rightQ,mod)*(rightZ+rightQ*div2))%mod
        ans = (ans+left*right)%mod
print(ans)