# https://scrapbox.io/bakamono1357-59364817/yukicoder_contest_377_D_-_Re:010
# dp[Sのi文字目まで見て][010のj文字目まで作る]総数

S = input()
N = len(S)
mod = 998244353
 
dp = [[0] * (3+1) for i in range(N+1)]
dp[0][0] = 1

for i in range(1, N+1):
    new = S[i-1]
    if new == '?':
        multiplier = 2
    else:
        multiplier = 1
        
    for j in range(4):
        # ?ならこれまでのパターンの2倍が使える
        dp[i][j] = dp[i-1][j]*multiplier
    if new == '0' or new == '?':
        # 010の1文字目と3文字目で1文字増える
        dp[i][1] += dp[i-1][0]
        dp[i][3] += dp[i-1][2]
    if new == '1' or new == '?':
        # 010の2文字目で1文字増える
        dp[i][2] += dp[i-1][1]
    for j in range(4):
        dp[i][j] %= mod
    #print(dp[i])

ans = dp[N][3]
print(ans)