#include <cstdio>
using namespace std;
typedef long long ll;
const ll mod=998244353;
ll a[105000];
ll b[105000];
int n;
int main()
{
    int t;
    scanf("%d",&t);
    while(t--)
    {
        scanf("%d",&n);
        for(int i=1;i<=n;i++)
        {
            scanf("%lld",&a[i]);
        }
        for(int i=1;i<=n;i++)
        {
            scanf("%lld",&b[i]);
        }
        bool ok=true;
        ll ans=1;
        int cnt=0;
        if(a[1]!=b[1]){
            printf("0\n");
            continue;
        }
        if(n==1){
            printf("1\n");
            continue;
        }
        for(int i=2;i<=n;i++)
        {
            if(a[i]>a[i-1]){ok=false;break;}
            if(b[i]<b[i-1]){ok=false;break;}
            if(a[i]!=a[i-1]&&b[i]!=b[i-1]){ok=false;break;}
            if(a[i]==a[i-1]&&b[i]==b[i-1]){
                ans=(ans*cnt)%mod;
                cnt--;
                if(cnt<0){
                    ok=false;
                    
                    break;
                }
                else continue;
            }
            if(a[i]!=a[i-1])
            {
                int tmp=a[i-1]-a[i];
                cnt+=(tmp-1);
            }
            else if(b[i]!=b[i-1])
            {
                int tmp=b[i]-b[i-1];
                cnt+=(tmp-1);
            }
        }
        if(!ok)printf("0\n");
        else printf("%lld\n",ans);
    }
    return 0;
}