#include <stdio.h>
#include <string.h>
#include <set>
#include <math.h>
#include <algorithm>
using namespace std ;

typedef long long LL ;

#define clr( a , x ) memset ( a , x , sizeof a )
#define ls ( o << 1 )
#define rs ( o << 1 | 1 )
#define root 1 , 1 , n
#define lson ls , l , mid
#define rson rs , mid + 1 , r

const int MAXN = 100005 ;
const int MAXE = 200005 ;
const LL INF = 1e18 ;
const int mod = 998244353 ;

int minv[MAXN << 2] ;
int zero[MAXN << 2] ;
int b[MAXN] , c[MAXN] ;
int a[MAXN] ;

void solve () {
    int n , ok = 1 ;
    scanf ( "%d" , &n ) ;
    b[0] = n + 1 ;
    for ( int i = 1 ; i <= n ; ++ i ) {
        scanf ( "%d" , &b[i] ) ;
        if ( b[i] > b[i - 1] ) ok = 0 ;
    }
    c[0] = 0 ;
    for ( int i = 1 ; i <= n ; ++ i ) {
        scanf ( "%d" , &c[i] ) ;
        if ( c[i] < c[i - 1] ) ok = 0 ;
    }
    if ( b[1] != c[1] ) ok = 0 ;
    if ( !ok ) {
        printf ( "0\n" ) ;
        return ;
    }
    a[1] = b[1] ;
    int cnt = 0 , ans = 1 ;
    for ( int i = 2 ; i <= n ; ++ i ) {
        if ( b[i] == b[i - 1] ) {
            if ( c[i] == c[i - 1] ) {
                ans = 1LL * ans * cnt % mod ;
                cnt -- ;
                if ( cnt < 0 ) ok = 0 ;
            } else {
                cnt += c[i] - c[i - 1] - 1 ;
            }
        } else {
            if ( c[i] == c[i - 1] ) {
                cnt += b[i - 1] - b[i] - 1 ;
            } else {
                ok = 0 ;
                ans = 0 ;
                break ;
            }
        }
    }
    if ( !ok ) printf ( "0\n" ) ;
    else printf ( "%d\n" , ans ) ;
}

int main () {
    int T ;
    scanf ( "%d" , &T ) ;
    getchar () ;
    for ( int i = 1 ; i <= T ; ++ i ) {
        solve () ;
    }
    return 0 ;
}