using System;
using System.Collections.Generic;
using System.Linq;
using System.Linq.Expressions;
using System.IO;
using System.Text;
using System.Diagnostics;
using static util;
using P = pair<int, int>;
using Binary = System.Func<System.Linq.Expressions.ParameterExpression, System.Linq.Expressions.ParameterExpression,
System.Linq.Expressions.BinaryExpression>;
using Unary = System.Func<System.Linq.Expressions.ParameterExpression, System.Linq.Expressions.UnaryExpression>;
class Program
{
static StreamWriter sw = new StreamWriter(Console.OpenStandardOutput()) { AutoFlush = false };
static Scan sc = new Scan();
const int M = 1000000007;
// const int M = 998244353;
const long LM = (long)1e18;
const double eps = 1e-11;
static readonly int[] dd = { 0, 1, 0, -1, 0 };
static void Main()
{
int n = sc.Int;
var a = new int[n];
var b = new int[n];
for (int i = 0; i < n; i++)
{
a[i] = sc.Int;
}
for (int i = 0; i < n; i++)
{
b[i] = sc.Int;
}
Array.Sort(a);
Array.Sort(b);
int ai = 0, bi = 0;
int sum = 0;
long ans = 1;
for (int i = 0; i < n * 2; i++)
{
if (bi == n || ai < n && a[ai] < b[bi]) {
++ai;
if (sum < 0)
ans = ans * -sum % M;
++sum;
}
else {
++bi;
if (sum > 0)
ans = ans * sum % M;
--sum;
}
}
Prt(ans);
sw.Flush();
}
static void DBG(string a) => Console.WriteLine(a);
static void DBG<T>(IEnumerable<T> a) => DBG(string.Join(" ", a));
static void DBG(params object[] a) => DBG(string.Join(" ", a));
static void Prt(string a) => sw.WriteLine(a);
static void Prt<T>(IEnumerable<T> a) => Prt(string.Join(" ", a));
static void Prt(params object[] a) => Prt(string.Join(" ", a));
}
class pair<T, U> : IComparable<pair<T, U>> where T : IComparable<T> where U : IComparable<U>
{
public T v1;
public U v2;
public pair(T v1, U v2) {
this.v1 = v1;
this.v2 = v2;
}
public int CompareTo(pair<T, U> a) => v1.CompareTo(a.v1) != 0 ? v1.CompareTo(a.v1) : v2.CompareTo(a.v2);
public override string ToString() => v1 + " " + v2;
}
static class util
{
public static pair<T, T> make_pair<T>(this IList<T> l) where T : IComparable<T> => make_pair(l[0], l[1]);
public static pair<T, U> make_pair<T, U>(T v1, U v2) where T : IComparable<T> where U : IComparable<U> => new pair<T, U>(v1, v2);
public static T sqr<T>(T a) => Operator<T>.Multiply(a, a);
public static T Max<T>(params T[] a) => a.Max();
public static T Min<T>(params T[] a) => a.Min();
public static void swap<T>(ref T a, ref T b) { var t = a; a = b; b = t; }
public static void swap<T>(this IList<T> a, int i, int j) { var t = a[i]; a[i] = a[j]; a[j] = t; }
public static T[] copy<T>(this IList<T> a) {
var ret = new T[a.Count];
for (int i = 0; i < a.Count; i++) ret[i] = a[i];
return ret;
}
}
static class Operator<T>
{
static readonly ParameterExpression x = Expression.Parameter(typeof(T), "x");
static readonly ParameterExpression y = Expression.Parameter(typeof(T), "y");
public static readonly Func<T, T, T> Add = Lambda(Expression.Add);
public static readonly Func<T, T, T> Subtract = Lambda(Expression.Subtract);
public static readonly Func<T, T, T> Multiply = Lambda(Expression.Multiply);
public static readonly Func<T, T, T> Divide = Lambda(Expression.Divide);
public static readonly Func<T, T> Plus = Lambda(Expression.UnaryPlus);
public static readonly Func<T, T> Negate = Lambda(Expression.Negate);
public static Func<T, T, T> Lambda(Binary op) => Expression.Lambda<Func<T, T, T>>(op(x, y), x, y).Compile();
public static Func<T, T> Lambda(Unary op) => Expression.Lambda<Func<T, T>>(op(x), x).Compile();
}
class Scan
{
public int Int => int.Parse(Str);
public long Long => long.Parse(Str);
public double Double => double.Parse(Str);
public string Str => Console.ReadLine().Trim();
public pair<T, U> Pair<T, U>() where T : IComparable<T> where U : IComparable<U>
{ T a; U b; Multi(out a, out b); return make_pair(a, b); }
public int[] IntArr => StrArr.Select(int.Parse).ToArray();
public long[] LongArr => StrArr.Select(long.Parse).ToArray();
public double[] DoubleArr => StrArr.Select(double.Parse).ToArray();
public string[] StrArr => Str.Split(new []{' '}, System.StringSplitOptions.RemoveEmptyEntries);
bool eq<T, U>() => typeof(T).Equals(typeof(U));
T ct<T, U>(U a) => (T)Convert.ChangeType(a, typeof(T));
T cv<T>(string s) => eq<T, int>() ? ct<T, int>(int.Parse(s))
: eq<T, long>() ? ct<T, long>(long.Parse(s))
: eq<T, double>() ? ct<T, double>(double.Parse(s))
: eq<T, char>() ? ct<T, char>(s[0])
: ct<T, string>(s);
public void Multi<T>(out T a) => a = cv<T>(Str);
public void Multi<T, U>(out T a, out U b)
{ var ar = StrArr; a = cv<T>(ar[0]); b = cv<U>(ar[1]); }
public void Multi<T, U, V>(out T a, out U b, out V c)
{ var ar = StrArr; a = cv<T>(ar[0]); b = cv<U>(ar[1]); c = cv<V>(ar[2]); }
public void Multi<T, U, V, W>(out T a, out U b, out V c, out W d)
{ var ar = StrArr; a = cv<T>(ar[0]); b = cv<U>(ar[1]); c = cv<V>(ar[2]); d = cv<W>(ar[3]); }
public void Multi<T, U, V, W, X>(out T a, out U b, out V c, out W d, out X e)
{ var ar = StrArr; a = cv<T>(ar[0]); b = cv<U>(ar[1]); c = cv<V>(ar[2]); d = cv<W>(ar[3]); e = cv<X>(ar[4]); }
public void Multi<T, U, V, W, X, Y>(out T a, out U b, out V c, out W d, out X e, out Y f)
{ var ar = StrArr; a = cv<T>(ar[0]); b = cv<U>(ar[1]); c = cv<V>(ar[2]); d = cv<W>(ar[3]); e = cv<X>(ar[4]); f = cv<Y>(ar[5]); }
}
static class mymath
{
public static long Mod = 1000000007;
public static bool isprime(long a) {
if (a < 2) return false;
for (long i = 2; i * i <= a; i++) if (a % i == 0) return false;
return true;
}
public static bool[] sieve(int n) {
var p = new bool[n + 1];
for (int i = 2; i <= n; i++) p[i] = true;
for (int i = 2; i * i <= n; i++) if (p[i]) for (int j = i * i; j <= n; j += i) p[j] = false;
return p;
}
public static List<int> getprimes(int n) {
var prs = new List<int>();
var p = sieve(n);
for (int i = 2; i <= n; i++) if (p[i]) prs.Add(i);
return prs;
}
public static long[][] E(int n) {
var ret = new long[n][];
for (int i = 0; i < n; i++) { ret[i] = new long[n]; ret[i][i] = 1; }
return ret;
}
public static double[][] dE(int n) {
var ret = new double[n][];
for (int i = 0; i < n; i++) { ret[i] = new double[n]; ret[i][i] = 1; }
return ret;
}
public static long[][] pow(long[][] A, long n) {
if (n == 0) return E(A.Length);
var t = pow(A, n / 2);
if ((n & 1) == 0) return mul(t, t);
return mul(mul(t, t), A);
}
public static double[][] pow(double[][] A, long n) {
if (n == 0) return dE(A.Length);
var t = pow(A, n / 2);
if ((n & 1) == 0) return mul(t, t);
return mul(mul(t, t), A);
}
public static double dot(double[] x, double[] y) {
int n = x.Length;
double ret = 0;
for (int i = 0; i < n; i++) ret += x[i] * y[i];
return ret;
}
public static double _dot(double[] x, double[] y) {
int n = x.Length;
double ret = 0, r = 0;
for (int i = 0; i < n; i++) {
double s = ret + (x[i] * y[i] + r);
r = (x[i] * y[i] + r) - (s - ret);
ret = s;
}
return ret;
}
public static long dot(long[] x, long[] y) {
int n = x.Length;
long ret = 0;
for (int i = 0; i < n; i++) ret = (ret + x[i] * y[i]) % Mod;
return ret;
}
public static T[][] trans<T>(T[][] A) {
int n = A[0].Length, m = A.Length;
var ret = new T[n][];
for (int i = 0; i < n; i++) { ret[i] = new T[m]; for (int j = 0; j < m; j++) ret[i][j] = A[j][i]; }
return ret;
}
public static double[] mul(double a, double[] x) {
int n = x.Length;
var ret = new double[n];
for (int i = 0; i < n; i++) ret[i] = a * x[i];
return ret;
}
public static long[] mul(long a, long[] x) {
int n = x.Length;
var ret = new long[n];
for (int i = 0; i < n; i++) ret[i] = a * x[i] % Mod;
return ret;
}
public static double[] mul(double[][] A, double[] x) {
int n = A.Length;
var ret = new double[n];
for (int i = 0; i < n; i++) ret[i] = dot(x, A[i]);
return ret;
}
public static long[] mul(long[][] A, long[] x) {
int n = A.Length;
var ret = new long[n];
for (int i = 0; i < n; i++) ret[i] = dot(x, A[i]);
return ret;
}
public static double[][] mul(double a, double[][] A) {
int n = A.Length;
var ret = new double[n][];
for (int i = 0; i < n; i++) ret[i] = mul(a, A[i]);
return ret;
}
public static long[][] mul(long a, long[][] A) {
int n = A.Length;
var ret = new long[n][];
for (int i = 0; i < n; i++) ret[i] = mul(a, A[i]);
return ret;
}
public static double[][] mul(double[][] A, double[][] B) {
int n = A.Length;
var Bt = trans(B);
var ret = new double[n][];
for (int i = 0; i < n; i++) ret[i] = mul(Bt, A[i]);
return ret;
}
public static long[][] mul(long[][] A, long[][] B) {
int n = A.Length;
var Bt = trans(B);
var ret = new long[n][];
for (int i = 0; i < n; i++) ret[i] = mul(Bt, A[i]);
return ret;
}
public static long[] add(long[] x, long[] y) {
int n = x.Length;
var ret = new long[n];
for (int i = 0; i < n; i++) ret[i] = (x[i] + y[i]) % Mod;
return ret;
}
public static long[][] add(long[][] A, long[][] B) {
int n = A.Length;
var ret = new long[n][];
for (int i = 0; i < n; i++) ret[i] = add(A[i], B[i]);
return ret;
}
public static long pow(long a, long b) {
if (a >= Mod) return pow(a % Mod, b);
if (a == 0) return 0;
if (b == 0) return 1;
var t = pow(a, b / 2);
if ((b & 1) == 0) return t * t % Mod;
return t * t % Mod * a % Mod;
}
public static long inv(long a) => pow(a, Mod - 2);
public static long gcd(long a, long b) {
while (b > 0) { var t = a % b; a = b; b = t; } return a;
}
// a x + b y = gcd(a, b)
public static long extgcd(long a, long b, out long x, out long y) {
long g = a; x = 1; y = 0;
if (b > 0) { g = extgcd(b, a % b, out y, out x); y -= a / b * x; }
return g;
}
public static long lcm(long a, long b) => a / gcd(a, b) * b;
static long[] facts;
public static long[] setfacts(int n) {
facts = new long[n + 1];
facts[0] = 1;
for (int i = 0; i < n; i++) facts[i + 1] = facts[i] * (i + 1) % Mod;
return facts;
}
public static long comb(int n, int r) {
if (n < 0 || r < 0 || r > n) return 0;
if (n - r < r) r = n - r;
if (r == 0) return 1;
if (r == 1) return n;
if (facts != null && facts.Length > n) return facts[n] * inv(facts[r]) % Mod * inv(facts[n - r]) % Mod;
int[] numer = new int[r], denom = new int[r];
for (int k = 0; k < r; k++) { numer[k] = n - r + k + 1; denom[k] = k + 1; }
for (int p = 2; p <= r; p++) {
int piv = denom[p - 1];
if (piv > 1) {
int ofst = (n - r) % p;
for (int k = p - 1; k < r; k += p) { numer[k - ofst] /= piv; denom[k] /= piv; }
}
}
long ret = 1;
for (int k = 0; k < r; k++) if (numer[k] > 1) ret = ret * numer[k] % Mod;
return ret;
}
public static long[][] getcombs(int n) {
var ret = new long[n + 1][];
for (int i = 0; i <= n; i++) {
ret[i] = new long[i + 1];
ret[i][0] = ret[i][i] = 1;
for (int j = 1; j < i; j++) ret[i][j] = (ret[i - 1][j - 1] + ret[i - 1][j]) % Mod;
}
return ret;
}
// nC0, nC2, ..., nCn
public static long[] getcomb(int n) {
var ret = new long[n + 1];
ret[0] = 1;
for (int i = 0; i < n; i++) ret[i + 1] = ret[i] * (n - i) % Mod * inv(i + 1) % Mod;
return ret;
}
}