/*
 * C[i] = C[A[i]] であるような i について、
 * C[i] = K が成り立つとしたときの答えに K をかけたものを出力すれば良いです。
 * 
 * C[i] = K であるような i の個数が s 個だとします。
 * そのような i に対する A[i] の場合の数は (N - s)^{s - 1}s^{2} です。
 * 
 * C[i] = a (!= K) であるような i の個数が t 個だとします。
 * そのような　i に対する A[i] の場合の数は (N - t)^t です。
 * 
 * よって、
 * f(x) = (N - t)^{t} * x^{t} / t!
 * g(x) = (N - s)^{s - 1} * s^{2} * x^{s} / s!
 * であるとすると、答えは
 * N![x^{N}]f^{K - 1}g
 * と表せます。
 * 
 * これは exp, log を用いて時間計算量 O(N log(N)) で求められます。
 *
 */


#include <bits/stdc++.h>
using namespace std;
using ll=long long;
#define rep(i,a,b) for (int i=(int)(a);i<(int)(b);i++)
#include <atcoder/convolution>

namespace po167{
// |f| = |g| = 2 ^ n
    template<class T>
    std::vector<T> FPS_cyclic_convolution(std::vector<T> f, std::vector<T> g){
        atcoder::internal::butterfly(f);
        atcoder::internal::butterfly(g);
        for (int i = 0; i < (int)f.size(); i++) f[i] *= g[i];
        atcoder::internal::butterfly_inv(f);
        T iz = (T)(1) / (T)(f.size());
        for (int i = 0; i < (int)f.size(); i++) f[i] *= iz;
        return f;
    }
}

namespace po167{
// return f'
    template <class T>
    std::vector<T> FPS_differential(std::vector<T> f){
        if (f.empty()) return f;
        for (int i = 0; i < (int)f.size() - 1; i++){
            f[i] = f[i + 1] * (T)(i + 1);
        }
        f.pop_back();
        return f;
    }
}

namespace po167{
    template <class T>
    std::vector<T> FPS_integral(std::vector<T> f){
        if (f.empty()) return f;
        std::vector<T> num_inv((int)f.size() + 1);
        num_inv[0] = 1;
        num_inv[1] = 1;
        auto m = T::mod();
        for (int i = 2; i <= (int)f.size(); i++){
            num_inv[i] = (0 - num_inv[m % i]) * (T)(m / i);
        }
        f.reserve((int)f.size() + 1);
        f.push_back(0);
        for (int i = (int)f.size() - 1; i > 0; i--){
            f[i] = f[i - 1] * num_inv[i];
        }
        f[0] = 0;
        return f;
    }
}

namespace po167{
// return 1 / f
    template <class T>
    std::vector<T> FPS_inv(std::vector<T> f, int len = -1){
        if (len == -1) len = f.size();
        assert(f[0] != 0);
        std::vector<T> g = {1 / f[0]};
        int s = 1;
        while(s < len){
            // g = 2g_s - f(g_s)^2 (mod x ^ (2 * s))
            // g = g - (fg - 1)g
            // (fg - 1) = 0 (mod x ^ (s))
            std::vector<T> n_g(s * 2, 0);
            std::vector<T> f_s(s * 2, 0);
            g.resize(s * 2);
            for (int i = 0; i < s * 2; i++){
                if (int(f.size()) > i) f_s[i] = f[i];
                n_g[i] = g[i];
            }
            atcoder::internal::butterfly(g);
            atcoder::internal::butterfly(f_s);
            for (int i = 0; i < s * 2; i++){
                f_s[i] *= g[i];
            }
            atcoder::internal::butterfly_inv(f_s);
            T iz = 1 / (T)(s * 2);
            for (int i = s; i < s * 2; i++){
                f_s[i] *= iz;
            }
            for (int i = 0; i < s; i++){
                f_s[i] = 0;
            }
            atcoder::internal::butterfly(f_s);
            for (int i = 0; i < s * 2; i++){
                f_s[i] *= g[i];
            }
            atcoder::internal::butterfly_inv(f_s);
            for (int i = s; i < s * 2; i++){
                n_g[i] -= f_s[i] * iz;
            }
            std::swap(n_g, g);
            s *= 2;
        }
        g.resize(len);
        return g;
    }
}

namespace po167{
    template<class T>
    std::vector<T> FPS_exp(std::vector<T> f, int len = -1){
        if (len == -1) len = f.size();
        if (len == 0) return {};
        if (len == 1) return {T(1)};
        assert(!f.empty() && f[0] == 0);
        int s = 1;
        // simple
        std::vector<T> g = {T(1)};
        while (s < len){
            // g' / g
            // A * B
            std::vector<T> A = g, B = g;
            A = FPS_differential(A);
            B = FPS_inv(B, 2 * s);
            A.resize(2 * s);
            A = FPS_cyclic_convolution(A, B);
            A.pop_back();
            A = FPS_integral(A);
            for (int i = 0; i < s; i++) A[i] = 0;
            for (int i = s; i < s * 2; i++) A[i] = (i < (int)f.size() ? f[i] : 0) - A[i];
            // g_hat = g (1 - g + f)
            // g += B = g * A
            g.resize(2 * s);
            B = FPS_cyclic_convolution(A, g);
            for (int i = s; i < s * 2; i++) g[i] = B[i];
            s *= 2;
        }
        g.resize(len);
        return g;
    }
}

namespace po167{
    template<class T>
    std::vector<T> FPS_log(std::vector<T> f, int len = -1){
        if (len == -1) len = f.size();
        if (len == 0) return {};
        if (len == 1) return {T(0)};
        assert(!f.empty() && f[0] == 1);
        std::vector<T> res = atcoder::convolution(FPS_differential(f), FPS_inv(f, len));
        res.resize(len - 1);
        return FPS_integral(res);
    }
}

namespace po167{
    template<class T>
    std::vector<T> FPS_pow(std::vector<T> f,long long M, int len = -1){
        if (len == -1) len = f.size();
        std::vector<T> res(len, 0);
        if (M == 0){
            res[0] = 1;
            return res;
        }
        for (int i = 0; i < (int)f.size(); i++){
            if (f[i] == 0) continue;
            if (i > (len - 1) / M) break;
            std::vector<T> g((int)f.size() - i);
            T v = (T)(1) / (T)(f[i]);
            for (int j = i; j < (int)f.size(); j++){
                g[j - i] = f[j] * v;
            }
            long long zero = i * M;
            if (i) len -= i * M;
            g = FPS_log(g, len);
            for (T &x : g) x *= M;
            g = FPS_exp(g, len);
            v = (T)(1) / v;
            T c = 1;
            while (M){
                if (M & 1) c = c * v;
                v = v * v;
                M >>= 1;
            }
            for (int j = 0; j < len; j++) res[j + zero] = g[j] * c;
            return res;
        }
        return res;
    }
}

using mint = atcoder::modint998244353;

int main() {
    int N;
    ll K;
    cin >> N >> K;
    vector<mint> fact(N + 1, 1), invfact(N + 1);
    rep(i, 0, N) fact[i + 1] = fact[i] * (i + 1);
    invfact[N] = fact[N].inv();
    for (int i = N; i > 0; i--){
        invfact[i - 1] = invfact[i] * i;
    }
    vector<mint> f(N + 1);
    rep(i, 0, N + 1){
        f[i] = invfact[i];
        f[i] *= ((mint)(N - i)).pow(i);
    }
    f = po167::FPS_pow(f, K - 1);

    mint ans = 0;
    rep(i, 1, N + 1){
        mint tmp = f[N - i];
        tmp *= invfact[i];
        tmp *= ((mint)(N - i)).pow(i - 1);
        tmp *= i;
        tmp *= i;
        ans += tmp;
    }
    ans *= fact[N];
    ans *= K;
    cout << ans.val() << "\n";
}