//清楚姐姐带带我 不能用dp 取模影响的答案计算
#include<bits/stdc++.h>
using namespace std;
#define ll long long
ll mod = 19980829;
ll MAXX = 0x3f3f3f3f;//当大于int范围时再取模
int main() {
    ll n; cin >> n;
    bool ok = 1;
    ll res = 0;
    for (int i = 1; i <= n; i++) {
        ll x, y; cin >> x >> y;
        if (ok) {//没有大于int范围 不需要取模 正常比较即可
            if (res + x > res * y) {
                res = res + x;
            }
            else res = res * y;
            if (res > MAXX)ok = 0;//当大于int范围时取模一次后面都乘法值最大
        }
        else {
            res = res % mod;
            if (y <= 1) {//<=1 加法
                res = (res + x) % mod;
            }
            else {//>=1 乘法
                res = (res * y) % mod;
            }
        }
    }
    cout << res << endl;
    return 0;
}


//MoonLight的运算问题  取模时乘法和加法没法直接比较 乘一次后面都是乘
#include<bits/stdc++.h>
#define int long long
using namespace std;
const int N = 1e5 + 10, mod = 998244353;
int a[N];
void slove()
{
    int n;
    cin >> n;
    for (int i = 1; i <= n; i++)cin >> a[i];
    int x = 0, f = 0;
    for (int i = 1; i <= n; i++)
    {
        if (a[i])//等于0时不操作
        {
            if (a[i] > 1 && f)//x已经大于1 进入乘法操作
            {
                x = x * a[i] % mod;
            }
            else
            {
                if (x + a[i] > 1)f = 1;//当x>1 开始进入乘法操作
                x = (x + a[i]) % mod;
            }
        }
    }
    cout << x << endl;
}
signed main()
{
    ios::sync_with_stdio(false);
    cin.tie(0), cout.tie(0);
    int t;
    cin >> t;
    while (t--)
    {
        slove();
    }
    return 0;
}