using System;
using static System.Console;
using System.Linq;
using System.Collections.Generic;
class Program
{
    static int NN => int.Parse(ReadLine());
    static int[] NList => ReadLine().Split().Select(int.Parse).ToArray();
    public static void Main()
    {
        Solve();
    }
    static void Solve()
    {
        var s = ReadLine();
        WriteLine(Count010(s));
    }
    static long Count010(string s)
    {
        var mod = 998_244_353;
        var dp = new long[3][];
        for (var i = 0; i < dp.Length; ++i) dp[i] = new long[s.Length];
        var count = new long[s.Length];
        count[0] = s[0] == '?' ? 2 : 1;
        if (s[0] != '1') dp[0][0] = 1;
        for (var i = 1; i < s.Length; ++i)
        {
            if (s[i] == '0')
            {
                dp[0][i] = (dp[0][i - 1] + count[i - 1]) % mod;
                dp[1][i] = dp[1][i - 1];
                dp[2][i] = (dp[2][i - 1] + dp[1][i - 1]) % mod;
                count[i] = count[i - 1];
            }
            else if (s[i] == '1')
            {
                dp[0][i] = dp[0][i - 1];
                dp[1][i] = (dp[1][i - 1] + dp[0][i - 1]) % mod;
                dp[2][i] = dp[2][i - 1];
                count[i] = count[i - 1];
            }
            else
            {
                dp[0][i] = (dp[0][i - 1] * 2 + count[i - 1]) % mod;
                dp[1][i] = (dp[1][i - 1] * 2 + dp[0][i - 1]) % mod;
                dp[2][i] = (dp[2][i - 1] * 2 + dp[1][i - 1]) % mod;
                count[i] = count[i - 1] * 2 % mod;
            }
        }
        return dp[2].Last();
    }
}