// Validator
#include <algorithm>
#include <cassert>
#include <iostream>
#include <vector>
using namespace std;

#include "testlib.h"

#include <atcoder/modint>
#include <atcoder/convolution>
using mint = atcoder::modint998244353;

template <typename modint> struct acl_fac {
    std::vector<modint> facs, facinvs;
    acl_fac(int N) {
        assert(-1 <= N and N < modint::mod());
        facs.resize(N + 1, 1);
        for (int i = 1; i <= N; i++) facs[i] = facs[i - 1] * i;
        facinvs.assign(N + 1, facs.back().inv());
        for (int i = N; i > 0; i--) facinvs[i - 1] = facinvs[i] * i;
    }
    modint operator[](int i) const { return facs.at(i); }
    modint finv(int i) const { return facinvs.at(i); }
};

constexpr int max_n = 2000;
acl_fac<mint> fac(max_n);

int main(int argc, char *argv[]) {
    registerValidation(argc, argv);


    vector<mint> f(max_n + 1);
    for (int n = 1; n <= max_n; ++n) {
        f.at(n) = (n == 1 ? 1 : mint(n).pow(n - 2)) * n * n * fac.finv(n);
    }

    vector<vector<mint>> dp(max_n + 1);
    dp.at(0) = vector<mint>(max_n + 1);
    dp.at(0).at(0) = 1;

    for (int k = 1; k <= max_n; ++k) {
        dp.at(k) = atcoder::convolution(f, dp.at(k - 1));
        dp.at(k).resize(max_n + 1);
    }

    for (int k = 1; k <= max_n; ++k) {
        for (int n = k; n <= max_n; ++n) {
            if (k > 1) {
                dp.at(k).at(n) *= fac[n] * fac.finv(k) * mint(n).pow(2 * (k - 2));
            } else {
                dp.at(k).at(n) = (n > 1 ? mint(n).pow(n - 2) : 1);
            }
        }
    }

    vector<vector<mint>> answers(1);

    for (int n = 1; n <= max_n; ++n) {
        vector<mint> g(n);
        for (int i = 0; i < n; ++i) g.at(i) = dp.at(n - i).at(n) * fac[i] * (i % 2 ? -1 : 1);
        vector<mint> fac_trans(n);
        for (int i = 0; i < n; ++i) fac_trans.at(i) = fac.finv(i);
        reverse(g.begin(), g.end());
        g = atcoder::convolution(g, fac_trans);
        g.resize(n);
        reverse(g.begin(), g.end());
        for (int i = 0; i < n; ++i) g.at(i) *= fac.finv(i) * (i % 2 ? -1 : 1);
        answers.push_back(g);
    }

    int T = inf.readInt(1, 500000);
    inf.readEoln();
    while (T--) {
        const int n = inf.readInt(2, max_n);
        inf.readSpace();
        const int k = inf.readInt(0, n - 1);
        inf.readEoln();
        cout << answers.at(n).at(k).val() << '\n';
    }
    inf.readEof();
}