S = gets.chomp
MOD = 998244353

a, b, c, d = 1, 0, 0, 0
S.each_char do |ch|
    case ch
    when ?0
        d += c
        b += a
        a %= MOD
        d %= MOD
    when ?1
        c += b
        c %= MOD
    when ??
        a0, b0, c0, d0 = a, b + a, c, d + c
        a1, b1, c1, d1 = a, b, c + b, d
        a, b, c, d = (a0 + a1) % MOD, (b0 + b1) % MOD, (c0 + c1) % MOD, (d0 + d1) % MOD
    end
end

puts d