Code: Non-Descending Arrays

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<int, int> pii;
#define pb push_back
#define all(a) a.begin(), a.end()
#define sz(a) ((int)a.size())
#ifdef Doludu
template <typename T> ostream &operator<<(ostream &o, vector<T> vec) {
    o << "{";
    int f = 0;
    for (T i : vec)
        o << (f++ ? " " : "") << i;
    return o << "}";
}
void bug__(int c, auto... a) {
    cerr << "\e[1;" << c << "m";
    (..., (cerr << a << " "));
    cerr << "\e[0m" << endl;
}
#define bug_(c, x...) bug__(c, __LINE__, "[" + string(#x) + "]", x)
#define bug(x...) bug_(32, x)
#define bugv(x...) bug_(36, vector(x))
#define safe bug_(33, "safe")
#else
#define bug(x...) void(0)
#define bugv(x...) void(0)
#define safe void(0)
#endif
const int mod = 998244353, N = 100005;

int add(int a, int b) {
    a += b;
    if (a >= mod)
        a -= mod;
    return a;
}

void solve() {
    int n;
    cin >> n;
    vector<int> a(n), b(n);
    for (int i = 0; i < n; ++i)
        cin >> a[i];
    for (int i = 0; i < n; ++i)
        cin >> b[i];
    int dp0 = 1, dp1 = 1;
    for (int i = 1; i < n; ++i) {
        int nxt0 = 0, nxt1 = 0;
        if (a[i - 1] <= a[i] && b[i - 1] <= b[i]) {
            nxt0 = add(nxt0, dp0);
            nxt1 = add(nxt1, dp1);
        }
        if (a[i - 1] <= b[i] && b[i - 1] <= a[i]) {
            nxt0 = add(nxt0, dp1);
            nxt1 = add(nxt1, dp0);
        }
        dp0 = nxt0, dp1 = nxt1;
    }
    cout << add(dp0, dp1) << "\n";
}

int main() {
    ios::sync_with_stdio(false), cin.tie(0);
    int t;
    cin >> t;
    while (t--) {
        solve();
    }
}