# もう一度実装してみる
# dp[Sのi文字目まで見て][010のj文字目まで作る]総数
# s = 0, 1, ?で異なる遷移

S = input()
N = len(S)
mod = 998244353

dp = [[0]*4 for i in range(N+1)]
dp[0][0] = 1

for i in range(1, N+1):
    s = S[i-1]
    if s == '0':
        for j in range(4):
            dp[i][j] += dp[i-1][j]
        dp[i][1] += dp[i-1][0]
        dp[i][3] += dp[i-1][2]
    elif s == '1':
        for j in range(4):
            dp[i][j] += dp[i-1][j]
        dp[i][2] += dp[i-1][1]
    elif s == '?':
        for j in range(4):
            dp[i][j] += dp[i-1][j]*2
        dp[i][1] += dp[i-1][0]
        dp[i][2] += dp[i-1][1]
        dp[i][3] += dp[i-1][2]
    for j in range(4):
        dp[i][j] %= mod
        
ans = dp[N][3]
print(ans)