#include<bits/stdc++.h>
#define LL long long
using namespace std;
const int maxn=1e5+7;
const int mod=1e9+7;
LL n;
LL p[maxn],q[maxn];
LL ans=1;
int main(){
	cin>>n;
	for(int i=1;i<=n;i++){
		cin>>p[i];
	}
	for(int i=1;i<=n;i++){
		cin>>q[i];
	}
	sort(p+1,p+n+1);
	sort(q+1,q+n+1);
	int l=n,cnt=n,tot=0;
	while(cnt>=1){
		if(q[l]>=p[cnt]&&l>=1){
			l--;
			tot++;
		}
		else{
			cnt--;
			ans=ans*tot%mod;
			tot--;
		}
	}
	LL t=0;
	cout<<max(t,ans);
	return 0;
}