// Slower C++ solution:
#include <iostream>

#include <algorithm>

#include <bitset>

#include <map>

#include <queue>

#include <set>

#include <stack>

#include <string>

#include <utility>

#include <vector>

#include <array>

#include <unordered_map>

#include <complex>

#include <deque>

#include <cassert>

#include <cmath>

#include <functional>

#include <iomanip>

#include <chrono>

#include <random>

#include <numeric>

#include <tuple>

#include <cstring>

using namespace std;



#define forr(x,arr) for(auto&& x:arr)

#define _overload3(_1,_2,_3,name,...) name

#define _rep2(i,n) _rep3(i,0,n)

#define _rep3(i,a,b) for(int i=int(a);i<int(b);++i)

#define rep(...) _overload3(__VA_ARGS__,_rep3,_rep2,)(__VA_ARGS__)

#define _rrep2(i,n) _rrep3(i,0,n)

#define _rrep3(i,a,b) for(int i=int(b)-1;i>=int(a);i--)

#define rrep(...) _overload3(__VA_ARGS__,_rrep3,_rrep2,)(__VA_ARGS__)

#define all(x) (x).begin(),(x).end()

#define bit(n) (1LL<<(n))

#define sz(x) ((int)(x).size())

#define TEN(n) ((ll)(1e##n))

#define fst first

#define snd second



string DBG_DLM(int &i){return(i++==0?"":", ");}

#define DBG_B(exp){int i=0;os<<"{";{exp;}os<<"}";return os;}

template<class T>ostream&operator<<(ostream&os,vector<T>v);

template<class T>ostream&operator<<(ostream&os,set<T>v);

template<class T>ostream&operator<<(ostream&os,queue<T>q);

template<class T>ostream&operator<<(ostream&os,priority_queue<T>q);

template<class T,class K>ostream&operator<<(ostream&os,pair<T,K>p);

template<class T,class K>ostream&operator<<(ostream&os,map<T,K>mp);

template<class T,class K>ostream&operator<<(ostream&os,unordered_map<T,K>mp);

template<int I,class TPL>void DBG(ostream&os,TPL t){}

template<int I,class TPL,class H,class...Ts>void DBG(ostream&os,TPL t){os<<(I==0?"":", ")<<get<I>(t);DBG<I+1,TPL,Ts...>(os,t);}

template<class T,class K>void DBG(ostream&os,pair<T,K>p,string delim){os<<"("<<p.first<<delim<<p.second<<")";}

template<class...Ts>ostream&operator<<(ostream&os,tuple<Ts...>t){os<<"(";DBG<0,tuple<Ts...>,Ts...>(os,t);os<<")";return os;}

template<class T,class K>ostream&operator<<(ostream&os,pair<T,K>p){DBG(os,p,", ");return os;}

template<class T>ostream&operator<<(ostream&os,vector<T>v){DBG_B(forr(t,v){os<<DBG_DLM(i)<<t;});}

template<class T>ostream&operator<<(ostream&os,set<T>s){DBG_B(forr(t,s){os<<DBG_DLM(i)<<t;});}

template<class T>ostream&operator<<(ostream&os,queue<T>q){DBG_B(for(;q.size();q.pop()){os<<DBG_DLM(i)<<q.front();});}

template<class T>ostream&operator<<(ostream&os,priority_queue<T>q){DBG_B(for(;q.size();q.pop()){os<<DBG_DLM(i)<<q.top();});}

template<class T,class K>ostream&operator<<(ostream&os,map<T,K>m){DBG_B(forr(p,m){os<<DBG_DLM(i);DBG(os,p,"->");});}

template<class T,class K>ostream&operator<<(ostream&os,unordered_map<T,K>m){DBG_B(forr(p,m){os<<DBG_DLM(i);DBG(os,p,"->");});}

#define DBG_OVERLOAD(_1,_2,_3,_4,_5,_6,macro_name,...)macro_name

#define DBG_LINE(){char s[99];sprintf(s,"line:%3d | ",__LINE__);cerr<<s;}

#define DBG_OUTPUT(v){cerr<<(#v)<<"="<<(v);}

#define DBG1(v,...){DBG_OUTPUT(v);}

#define DBG2(v,...){DBG_OUTPUT(v);cerr<<", ";DBG1(__VA_ARGS__);}

#define DBG3(v,...){DBG_OUTPUT(v);cerr<<", ";DBG2(__VA_ARGS__);}

#define DBG4(v,...){DBG_OUTPUT(v);cerr<<", ";DBG3(__VA_ARGS__);}

#define DBG5(v,...){DBG_OUTPUT(v);cerr<<", ";DBG4(__VA_ARGS__);}

#define DBG6(v,...){DBG_OUTPUT(v);cerr<<", ";DBG5(__VA_ARGS__);}

#define DEBUG0(){DBG_LINE();cerr<<endl;}

#ifdef LOCAL

#define out(...){DBG_LINE();DBG_OVERLOAD(__VA_ARGS__,DBG6,DBG5,DBG4,DBG3,DBG2,DBG1)(__VA_ARGS__);cerr<<endl;}

#else

#define out(...)

#endif



using ll=long long;

using pii=pair<int,int>;using pll=pair<ll,ll>;using pil=pair<int,ll>;using pli=pair<ll,int>;

using vs=vector<string>;using vvs=vector<vs>;using vvvs=vector<vvs>;

using vb=vector<bool>;using vvb=vector<vb>;using vvvb=vector<vvb>;

using vi=vector<int>;using vvi=vector<vi>;using vvvi=vector<vvi>;

using vl=vector<ll>;using vvl=vector<vl>;using vvvl=vector<vvl>;

using vd=vector<double>;using vvd=vector<vd>;using vvvd=vector<vvd>;

using vpii=vector<pii>;using vvpii=vector<vpii>;using vvvpii=vector<vvpii>;

template<class A,class B>bool amax(A&a,const B&b){return b>a?a=b,1:0;}

template<class A,class B>bool amin(A&a,const B&b){return b<a?a=b,1:0;}

ll ri(){ll l;cin>>l;return l;} string rs(){string s;cin>>s;return s;}



const int mod = 1e9+7;



template<int MOD> struct Mint {

	int x;

	Mint() : x(0) {}

	Mint(int y) : x(y >= 0 ? y % MOD : MOD - (-y) % MOD) {}

	Mint(int64_t sll) : x(sll % MOD) { if (x < 0) x += MOD; }

	Mint &operator+=(const Mint &rhs){ if((x += rhs.x) >= MOD) x -= MOD; return *this; }

	Mint &operator-=(const Mint &rhs){ if((x += MOD - rhs.x) >= MOD) x -= MOD; return *this; }

	Mint &operator*=(const Mint &rhs){ x = 1LL*x*rhs.x % MOD; return *this; }

	Mint &operator/=(const Mint &rhs){ x = (1LL*x*rhs.inv().x) % MOD; return *this; }

	Mint operator-() const { return Mint(-x); }

	Mint operator+(const Mint &rhs) const { return Mint(*this) += rhs; }

	Mint operator-(const Mint &rhs) const { return Mint(*this) -= rhs; }

	Mint operator*(const Mint &rhs) const { return Mint(*this) *= rhs; }

	Mint operator/(const Mint &rhs) const { return Mint(*this) /= rhs; }

	bool operator<(const Mint &rhs) const { return x < rhs.x; }

	Mint inv() const {

		assert(x != 0);

		signed a = x, b = MOD, u = 1, v = 0, t;

		while (b) { t = a / b; a -= t * b; swap(a, b); u -= t * v; swap(u, v); }

		return Mint(u);

	}

	Mint operator^(uint64_t t) const {

		Mint e = *this, res = 1;

		for(; t; e *= e, t>>=1) if (t & 1) res *= e;

		return res;

	}

};

template<int MOD> ostream &operator<<(ostream &os, const Mint<MOD> &rhs) { return os << rhs.x; }

template<int MOD> istream &operator>>(istream &is, Mint<MOD> &rhs) { int64_t s; is >> s; rhs = Mint<MOD>(s); return is; };



using mint = Mint<mod>;

using vm=vector<mint>;using vvm=vector<vm>;using vvvm=vector<vvm>;



template <typename T> struct BinaryIndexedTree0 {

	const int N;

	vector<T> val;



	BinaryIndexedTree0(int N) : N(N), val(N) {}



	T sum(int i) const {

		T s = 0;

		--i;

		if (i >= N) i = N - 1;

		for (; i >= 0; i = (i & (i + 1)) - 1) s += val[i];

		return s;

	}



	T sum(int l, int r) const {

		return sum(r) - sum(l);

	}



	void add(int i, T x) {

		for (; i < N; i |= i + 1) val[i] += x;

	}

};



int64_t powMod(int64_t x, int64_t y, int64_t mod) {

	int64_t r = 1, a = x % mod;

	while (y) {

		if (y & 1) r = (r * a) % mod;

		a = a * a % mod;

		y /= 2;

	}

	return r;

}



const int SET_FACT_MAX = 100005;

mint fact[SET_FACT_MAX];

mint revFact[SET_FACT_MAX];



void setFact() {

	const int N = SET_FACT_MAX;

	fact[0] = 1;

	for (int i = 1; i < N; i++) {

		fact[i] = fact[i - 1] * i;

	}

	revFact[N - 1] = fact[N - 1] ^ (mod - 2);

	for (int i = N - 2; i >= 0; i--) {

		revFact[i] = revFact[i + 1] * (i + 1);

	}

}



mint solve() {

	int n = ri();

	setFact();



	vector<int> A(n);

	rep(i, n) A[i] = ri();



	vector<int> B(n);

	rep(i, n) B[i] = ri();



	sort(all(A));

	sort(all(B));



	sort(all(A));

	sort(all(B));

 

	{

		A.emplace_back(2e9);

		B.emplace_back(2e9);

		int i = 0;

		int p = 0, q = 0;

		while (1) {

			if (A[p] < B[q]) {

				A[p++] = i++;

			}

			else if (A[p] > B[q]) {

				B[q++] = i++;

			}

			else {

				A.pop_back();

				B.pop_back();

				break;

			}

		}

	}

 

	out(A);

	out(B);



	BinaryIndexedTree0<int> ftA(n*2), ftB(n*2);

	forr(a, A) ftA.add(a, 1);

	forr(b, B) ftB.add(b, 1);



	mint ans = 1;



	rep(i, n) {

		int a = A[i];

		int b = B[i];

		out(i, a, b);

		int j = i;

		if (a < b) {

			for (; j < n && A[j] < B[j]; j++) {

				int cnt = ftA.sum(A[i], B[j]);

				out(i,j,A[i],B[j],cnt);

				cnt -= (j-i);

				ans *= cnt;

			}

		}

		else {

			for (; j < n && A[j] > B[j]; j++) {

				int cnt = ftB.sum(B[i], A[j]);

				out(i,j,B[i],A[j],cnt);

				cnt -= (j-i);

				ans *= cnt;

			}

		}

		i = j-1;

	}



	return ans;

}



void Main() {

	cout << solve() << endl;

}



signed main() {

	cin.tie(nullptr);

	ios::sync_with_stdio(false);

	Main();

	return 0;

}


// Faster C++ solution for the same problem (measured speedup: 2.8377096796882846x):
/* 解説を見た */



#include <iostream>

#include <algorithm>

#include <bitset>

#include <map>

#include <queue>

#include <set>

#include <stack>

#include <string>

#include <utility>

#include <vector>

#include <array>

#include <unordered_map>

#include <complex>

#include <deque>

#include <cassert>

#include <cmath>

#include <functional>

#include <iomanip>

#include <chrono>

#include <random>

#include <numeric>

#include <tuple>

#include <cstring>

using namespace std;



#define forr(x,arr) for(auto&& x:arr)

#define _overload3(_1,_2,_3,name,...) name

#define _rep2(i,n) _rep3(i,0,n)

#define _rep3(i,a,b) for(int i=int(a);i<int(b);++i)

#define rep(...) _overload3(__VA_ARGS__,_rep3,_rep2,)(__VA_ARGS__)

#define _rrep2(i,n) _rrep3(i,0,n)

#define _rrep3(i,a,b) for(int i=int(b)-1;i>=int(a);i--)

#define rrep(...) _overload3(__VA_ARGS__,_rrep3,_rrep2,)(__VA_ARGS__)

#define all(x) (x).begin(),(x).end()

#define bit(n) (1LL<<(n))

#define sz(x) ((int)(x).size())

#define TEN(n) ((ll)(1e##n))

#define fst first

#define snd second



string DBG_DLM(int &i){return(i++==0?"":", ");}

#define DBG_B(exp){int i=0;os<<"{";{exp;}os<<"}";return os;}

template<class T>ostream&operator<<(ostream&os,vector<T>v);

template<class T>ostream&operator<<(ostream&os,set<T>v);

template<class T>ostream&operator<<(ostream&os,queue<T>q);

template<class T>ostream&operator<<(ostream&os,priority_queue<T>q);

template<class T,class K>ostream&operator<<(ostream&os,pair<T,K>p);

template<class T,class K>ostream&operator<<(ostream&os,map<T,K>mp);

template<class T,class K>ostream&operator<<(ostream&os,unordered_map<T,K>mp);

template<int I,class TPL>void DBG(ostream&os,TPL t){}

template<int I,class TPL,class H,class...Ts>void DBG(ostream&os,TPL t){os<<(I==0?"":", ")<<get<I>(t);DBG<I+1,TPL,Ts...>(os,t);}

template<class T,class K>void DBG(ostream&os,pair<T,K>p,string delim){os<<"("<<p.first<<delim<<p.second<<")";}

template<class...Ts>ostream&operator<<(ostream&os,tuple<Ts...>t){os<<"(";DBG<0,tuple<Ts...>,Ts...>(os,t);os<<")";return os;}

template<class T,class K>ostream&operator<<(ostream&os,pair<T,K>p){DBG(os,p,", ");return os;}

template<class T>ostream&operator<<(ostream&os,vector<T>v){DBG_B(forr(t,v){os<<DBG_DLM(i)<<t;});}

template<class T>ostream&operator<<(ostream&os,set<T>s){DBG_B(forr(t,s){os<<DBG_DLM(i)<<t;});}

template<class T>ostream&operator<<(ostream&os,queue<T>q){DBG_B(for(;q.size();q.pop()){os<<DBG_DLM(i)<<q.front();});}

template<class T>ostream&operator<<(ostream&os,priority_queue<T>q){DBG_B(for(;q.size();q.pop()){os<<DBG_DLM(i)<<q.top();});}

template<class T,class K>ostream&operator<<(ostream&os,map<T,K>m){DBG_B(forr(p,m){os<<DBG_DLM(i);DBG(os,p,"->");});}

template<class T,class K>ostream&operator<<(ostream&os,unordered_map<T,K>m){DBG_B(forr(p,m){os<<DBG_DLM(i);DBG(os,p,"->");});}

#define DBG_OVERLOAD(_1,_2,_3,_4,_5,_6,macro_name,...)macro_name

#define DBG_LINE(){char s[99];sprintf(s,"line:%3d | ",__LINE__);cerr<<s;}

#define DBG_OUTPUT(v){cerr<<(#v)<<"="<<(v);}

#define DBG1(v,...){DBG_OUTPUT(v);}

#define DBG2(v,...){DBG_OUTPUT(v);cerr<<", ";DBG1(__VA_ARGS__);}

#define DBG3(v,...){DBG_OUTPUT(v);cerr<<", ";DBG2(__VA_ARGS__);}

#define DBG4(v,...){DBG_OUTPUT(v);cerr<<", ";DBG3(__VA_ARGS__);}

#define DBG5(v,...){DBG_OUTPUT(v);cerr<<", ";DBG4(__VA_ARGS__);}

#define DBG6(v,...){DBG_OUTPUT(v);cerr<<", ";DBG5(__VA_ARGS__);}

#define DEBUG0(){DBG_LINE();cerr<<endl;}

#ifdef LOCAL

#define out(...){DBG_LINE();DBG_OVERLOAD(__VA_ARGS__,DBG6,DBG5,DBG4,DBG3,DBG2,DBG1)(__VA_ARGS__);cerr<<endl;}

#else

#define out(...)

#endif



using ll=long long;

using pii=pair<int,int>;using pll=pair<ll,ll>;using pil=pair<int,ll>;using pli=pair<ll,int>;

using vs=vector<string>;using vvs=vector<vs>;using vvvs=vector<vvs>;

using vb=vector<bool>;using vvb=vector<vb>;using vvvb=vector<vvb>;

using vi=vector<int>;using vvi=vector<vi>;using vvvi=vector<vvi>;

using vl=vector<ll>;using vvl=vector<vl>;using vvvl=vector<vvl>;

using vd=vector<double>;using vvd=vector<vd>;using vvvd=vector<vvd>;

using vpii=vector<pii>;using vvpii=vector<vpii>;using vvvpii=vector<vvpii>;

template<class A,class B>bool amax(A&a,const B&b){return b>a?a=b,1:0;}

template<class A,class B>bool amin(A&a,const B&b){return b<a?a=b,1:0;}

ll ri(){ll l;cin>>l;return l;} string rs(){string s;cin>>s;return s;}



const int mod = 1e9+7;



ll solve() {

	int n = ri();



	vpii P(n*2);



	rep(i, n) P[i].fst = ri(), P[i].snd = 0;

	rep(i, n) P[n+i].fst = ri(), P[n+i].snd = 1;



	sort(all(P));



	vi C(2);



	ll ans = 1;



	forr(pp, P) {

		int t = pp.snd;

		if (C[1-t] == 0) {

			C[t]++;

		}

		else {

			(ans *= C[1-t]) %= mod;

			C[1-t]--;

		}

	}



	return ans;

}



void Main() {

	cout << solve() << endl;

}



signed main() {

	cin.tie(nullptr);

	ios::sync_with_stdio(false);

	Main();

	return 0;

}