#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 = 500;
        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 <algorithm>

template<long long MOD>
struct modint {
    modint() : x(0) {}
    modint(long long v) : x(v % MOD) {
        if (x < 0) x += MOD;
    }
    long long x;
    long long val() const { return x; }
    static constexpr long long mod() noexcept { return MOD; }
    friend modint operator+(modint a, modint b) { return a.x + b.x; }
    friend modint operator-(modint a, modint b) { return a.x - b.x; }
    friend modint operator*(modint a, modint b) { return a.x * b.x; }
    friend modint operator/(modint a, modint b) { return a.x * b.inv(); }
    friend modint operator+=(modint &a, modint b) { return a = a + b; }
    friend modint operator-=(modint &a, modint b) { return a = a - b; }
    friend modint operator*=(modint &a, modint b) { return a = a * b; }
    friend modint operator/=(modint &a, modint b) { return a = a / b; }
    friend bool operator==(modint a, modint b) {return a.x == b.x; }
    friend bool operator!=(modint a, modint b) {return a.x != b.x; }
    modint operator+() const { return *this; }
    modint operator-() const { return modint() - *this; }
    // ここまでがテンプレ
    // これ以降は必要に応じて

    modint pow(long long k) const {
        modint a = x, res = 1;
        while (k > 0) {
            if (k & 1) res *= a;
            a *= a;
            k >>= 1;
        }
        return res;
    }
    modint inv() const {
        long long a = x, b = MOD;
        long long u = 1, v = 0;
        while (b > 0) {
            long long t = a / b;
            a -= t * b;
            swap(a, b);
            u -= t * v;
            swap(u, v);
        }
        return u;
    }

    // ++a とか a-- とかを使うなら書く
    modint& operator++() {
        x++;
        if (x == MOD ) x = 0;
        return *this;
    }
    modint& operator--() {
        if (x == 0) x = MOD;
        x--;
        return *this;
    }
    modint operator++(int) {
        modint res = *this;
        ++*this;
        return res;
    }
    modint operator--(int) {
        modint res = *this;
        --*this;
        return res;
    }
};

using mint = modint<998244353>;

#include <iostream>

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';
    }
}