using System;
using static System.Console;
using System.Linq;
using System.Collections.Generic;

class Program
{
    static int NN => int.Parse(ReadLine());
    static double[] NList => ReadLine().Split().Select(double.Parse).ToArray();
    static double[][] NArr(long n) => Enumerable.Repeat(0, (int)n).Select(_ => NList).ToArray();
    public static void Main()
    {
        Solve();
    }
    static void Solve()
    {
        var n = NN;
        var s = ReadLine();
        var mod = 998_244_353;
        var ans = 0L;
        var dp = new long[3];
        for (var i = 0; i < n; ++i)
        {
            var ndp = new long[3];
            if (s[i] == '?')
            {
                ndp[0] += 4;
                ndp[1] += 3;
                ndp[2] += 3;
                for (var j = 0; j < 3; ++j)
                {
                    ndp[j] = (ndp[j] + dp[j] * 4 % mod) % mod;
                    ndp[(j + 1) % 3] = (ndp[(j + 1) % 3] + dp[j] * 3 % mod) % mod;
                    ndp[(j + 2) % 3] = (ndp[(j + 2) % 3] + dp[j] * 3 % mod) % mod;
                }
            }
            else
            {
                ndp[(s[i] - '0') % 3] += 1;
                for (var j = 0; j < 3; ++j) ndp[(j + s[i] - '0') % 3] = (ndp[(j + s[i] - '0') % 3] + dp[j]) % mod;
            }
            ans = (ans + ndp[0]) % mod;
            dp = ndp;
        }
        WriteLine(ans);
    }
}