#include <cstdio>
#include <cstring>
#include <algorithm>
#define i64 long long
#define MOD 998244353
#define N_MAX 100000
int T, n, m, i, l, r, x, a[N_MAX + 1], b[N_MAX + 1], c[N_MAX + 1];
i64 f[N_MAX + 1] = {1}, g[N_MAX + 1] = {1}, ans;
inline i64 pow(i64 a, int k)
{
    register i64 w = 1;
    for (a %= MOD; k; a = a * a % MOD, k >>= 1)
        if (k & 1) w = w * a % MOD;
    return w;
}
inline i64 inv(i64 a)
{
    return pow(a, MOD - 2);
}
int main()
{
    for (i = 1; i <= N_MAX; ++i)
        f[i] = f[i - 1] * i % MOD, g[i] = g[i - 1] * inv(i) % MOD;
    scanf("%d", &T);
    while (T--)
    {
        memset(a + 1, 0, n * sizeof (int));
        scanf("%d", &n);
        for (i = 1; i <= n; ++i)
            scanf("%d", &b[i]);
        for (i = 1; i <= n; ++i)
            scanf("%d", &c[i]);
        if (b[1] != c[1]) goto no;
        for (i = 2; i <= n; ++i)
            if (b[i] > b[i - 1] || c[i] < c[i - 1])
                goto no;
        for (i = 1; i <= n; ++i)
            if (b[i] != b[i - 1])
                a[i] = b[i];
        for (i = 1; i <= n; ++i)
            if (c[i] == c[i - 1]) continue;
            else if (!a[i]) a[i] = c[i];
            else if (a[i] != c[i]) goto no;
        ans = 1, m = 0;
        l = b[1], r = c[1];
        x = r - l;
        for (i = 2; i <= n; ++i)
        {
            if (a[i])
            {
                if (x < m) goto no;
                else ans = ans * f[x] % MOD * g[x - m] % MOD, x -= m, m = 0;
                x += l - b[i] + c[i] - r - 1, l = b[i], r = c[i];
            }
            else ++m;
        }
        if (x != m) goto no;
        else ans = ans * f[x] % MOD;
        printf("%d\n", (int) ans);
        continue;
no:        puts("0");
    }
    return 0;
}