#include <vector>
using namespace std;

template<typename mint>
struct prefix_binomial_sum {
    prefix_binomial_sum(int n) : size(n), b(0) {}
    mint get(int n, int k) {
        build();
        int m = n / b;
        mint res = table[m][k];
        m *= b;
        while (m < n) {
            res = 2 * res - binom(m, k);
            m++;
        }
        return res;
    }
private:
    int size, b;
    vector<mint> fac, finv;
    vector<vector<mint>> table;
    mint binom(int n, int k) {
        if (n < k) return mint();
        return fac[n] * finv[n - k] * finv[k];
    }
    void build() {
        if (b > 0) return;
        b = 450;
        fac.resize(size + 1);
        finv.resize(size + 1);
        table.reserve(size / b);
        fac[0] = 1;
        for (int i = 1; i <= size; i++) {
            fac[i] = i * fac[i - 1];
        }
        finv[size] = fac[size].inv();
        for (int i = size; i >= 1; i--) {
            finv[i - 1] = i * finv[i];
        }
        for (int i = 0; i * b <= size; i++) {
            vector<mint> v(size + 1);
            v[0] = 1;
            for (int j = 1; j <= size; j++) {
                v[j] = v[j - 1] + binom(b * i, j);
            }
            table.push_back(v);
        }
    }
};

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

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    prefix_binomial_sum<mint> C(200000);
    int T;
    cin >> T;
    while (T--) {
        int N, M;
        cin >> N >> M;
        mint ans = mint(2).pow(N) - 1;
        ans *= C.get(N - 1, M - 1);
        cout << ans.val() << '\n';
    }
}