#include <bits/stdc++.h>

using namespace std;

#define forn(i, n) for (int i = 0; i < int(n); i++)
#define fore(i, l, r) for (int i = int(l); i < int(r); i++)
#define sz(a) int((a).size())

typedef long long li;

const int MOD = 998244353;

int add(int a, int b){
    a += b;
    if (a >= MOD)
        a -= MOD;
    if (a < 0)
        a += MOD;
    return a;
}

int mul(int a, int b){
    return a * 1ll * b % MOD;
}

int binpow(int a, int b){
    int res = 1;
    while (b){
        if (b & 1)
            res = mul(res, a);
        a = mul(a, a);
        b >>= 1;
    }
    return res;
}

const int N = 4;

typedef array<array<int, N>, N> mat;

mat operator *(const mat &a, const mat &b){
    mat c;
    forn(i, N) forn(j, N) c[i][j] = 0;
    forn(i, N) forn(j, N) forn(k, N)
        c[i][j] = add(c[i][j], mul(a[i][k], b[k][j]));
    return c;
}

mat binpow(mat a, int b){
    mat res;
    forn(i, N) forn(j, N) res[i][j] = i == j;
    while (b){
        if (b & 1)
            res = res * a;
        a = a * a;
        b >>= 1;
    }
    return res;
}

void solve() {
    int n, m;
    cin >> n >> m;

    vector<int> opts(3);
    forn(res, 3) forn(st1, 2) forn(st2, 2){
        mat init;
        forn(i, N) forn(j, N) init[i][j] = 0;
        forn(i, 2) forn(j, 2) forn(k, 2){
            if (j + (i & k) == res){
                ++init[i * 2 + j][j * 2 + k];
            }
        }
        init = binpow(init, n - 2);
        forn(i, 2) forn(j, 2){
            if (j + (i & st1) == res && st1 + (j & st2) == res){
                opts[res] = add(opts[res], init[st1 * 2 + st2][i * 2 + j]);
            }
        }
    }

    vector<vector<int>> dp(31, vector<int>(2));
    dp[0][0] = 1;
    forn(i, 30){
        int c = (m >> i) & 1;
        if (c == 0){
            dp[i + 1][0] = add(dp[i + 1][0], mul(dp[i][0], opts[0]));
            dp[i + 1][1] = add(dp[i + 1][1], mul(dp[i][0], opts[2]));
            dp[i + 1][1] = add(dp[i + 1][1], mul(dp[i][1], opts[1]));
        }
        else{
            dp[i + 1][0] = add(dp[i + 1][0], mul(dp[i][0], opts[1]));
            dp[i + 1][0] = add(dp[i + 1][0], mul(dp[i][1], opts[0]));
            dp[i + 1][1] = add(dp[i + 1][1], mul(dp[i][1], opts[2]));
        }
    }
    cout << dp[30][0] << '\n';
}

int main() {
#ifdef _DEBUG
    freopen("input.txt", "r", stdin);
#endif
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);

    solve();
    return 0;
}