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 c = NList;
        var (n, t) = (c[0], c[1]);
        c = NList;
        var (k, l) = (c[0], c[1]);
        if (n == 1)
        {
            WriteLine(1);
            return;
        }
        var a = new long[1][];
        for (var i = 0; i < a.Length; ++i) a[i] = new long[t];
        a[0][0] = 1;
        var x = new long[t][];
        for (var i = 0; i < x.Length; ++i)
        {
            x[i] = new long[t];
            if (i == 0)
            {
                x[i][0] = (k - 1) * rev % mod;
                if (t == 2)
                {
                    x[i][1] = (7 - k) * rev % mod;
                }
                else
                {
                    x[i][1] = (l - k) * rev % mod;
                    x[i][t - 1] = (7 - l) * rev % mod;
                }
            }
            else x[i][i - 1] = 1;
        }
        var b = Matrix.Mul(a, Matrix.Pow(x, n - 1));
        WriteLine(b[0][0]);
    }
    static long mod = 998_244_353;
    static long rev = 166_374_059;
    class Matrix
    {
        // 行列の累乗
        public static long[][] Pow(long[][] m, long k)
        {
            var multi = m;
            var r = new long[m.Length][];
            for (var i = 0; i < m.Length; ++i)
            {
                r[i] = new long[m.Length];
                r[i][i] = 1;
            }
            while (k > 0)
            {
                if ((k & 1) == 1) r = Mul(r, multi);
                multi = Mul(multi, multi);
                k >>= 1;
            }
            return r;
        }
        // 行列の積
        public static long[][] Mul(long[][] x, long[][] y)
        {
            var r = new long[x.Length][];
            for (var i = 0; i < x.Length; ++i) r[i] = new long[y[0].Length];
            for (var i = 0; i < x.Length; ++i) for (var k = 0; k < x[0].Length; ++k)
            {
                for (var j = 0; j < y[0].Length; ++j) r[i][j] = (r[i][j] + x[i][k] * y[k][j]) % mod;
            }
            return r;
        }
    }
}