#include <bits/stdc++.h>

using namespace std;

#define int long long

const int MOD = 998244353;
const int INV2 = (MOD + 1) / 2;
const int MAX_N = 2e5 + 50;
const int BSIZE = 1;

int T, fact[MAX_N], inv[MAX_N], ans[MAX_N];

struct Query {
    int n, m, id;
    bool operator < (const Query& q) const {
        if (n / BSIZE != q.n / BSIZE)
            return n / BSIZE < q.n / BSIZE;
        return (n / BSIZE & 1) ? m < q.m : m > q.m;
    }
} q[MAX_N];

int qpow(int a, int k) {
    int res = 1;
    while (k) {
        if (k & 1)
            res = res * a % MOD;
        a = a * a % MOD;
        k >>= 1;
    }
    return res;   
}

inline int C(int n, int m) {
    if (n < m) return 0;
    return fact[n] * inv[m] % MOD * inv[n - m] % MOD;
}

signed main() {
    fact[0] = inv[0] = 1;
    for (int i = 1; i < MAX_N; i++) {
        fact[i] = fact[i - 1] * i % MOD;
        inv[i] = qpow(fact[i], MOD - 2);
    }
    cin >> T;
    for (int i = 1; i <= T; i++) {
        cin >> q[i].n >> q[i].m;
        q[i].n--, q[i].m--;
        q[i].id = i;
    }
    sort(q + 1, q + T + 1);
    int n = 0, m = 0, cur = 1;
    for (int i = 1; i <= T; i++) {
        while (n < q[i].n)
            cur = (cur * 2 - C(n++, m)) % MOD;
        while (n > q[i].n)
            cur = (cur + C(--n, m)) * INV2 % MOD;
        while (m < q[i].m)
            cur = (cur + C(n, ++m)) % MOD;
        while (m > q[i].m)
            cur = (cur - C(n, m--)) % MOD;
        ans[q[i].id] = (cur + MOD) * (qpow(2, n + 1) - 1) % MOD;
    }
    for (int i = 1; i <= T; i++)
        cout << ans[i] << '\n';
    return 0;
}