#include<cstdio>
#include<iostream>
#include<cstring>
#include<algorithm>
#define ull unsigned long long
#define ll long long
#define d double
using namespace std;
const int maxn=100233,modd=998244353;
int a[maxn],b[maxn],f[maxn];
int i,j,k,n,m;

int ra;char rx;
inline int read(){
    rx=getchar(),ra=0;
    while(rx<'0'||rx>'9')rx=getchar();
    while(rx>='0'&&rx<='9')ra*=10,ra+=rx-48,rx=getchar();return ra;
}
int main(){
    for(int T=read();T;T--){
        n=read();
        for(i=1;i<=n;i++)a[i]=read();
        for(i=1;i<=n;i++)b[i]=read();
        if(a[1]!=b[1]){puts("0");continue;}
        f[1]=1;
        for(i=2;i<=n;i++){
            if(a[i]==a[i-1]&&b[i]>b[i-1])f[i]=f[i-1];else
            if(a[i]<a[i-1]&&b[i]==b[i-1])f[i]=f[i-1];else
            if(a[i]==a[i-1]&&b[i]==b[i-1]&&b[i]-a[i]+1>=i)f[i]=1ll*f[i-1]*(b[i]-a[i]+1-(i-1))%modd;//,printf(" %d    %d\n",i,b[i]-a[i]+1);
            else break;
        }
        if(i<=n)puts("0");else printf("%d\n",f[n]);
    }
}