P10247 [AtCoder] CODE FESTIVAL 2016 Grand Final(Parallel) - 1D Matching
普及
题目描述

There are N computers and N sockets in a one-dimensional world. The coordinate of the i-th computer is a_i, and the coordinate of the i-th socket is b_i. It is guaranteed that these 2N coordinates are pairwise distinct.

Snuke wants to connect each computer to a socket using a cable. Each socket can be connected to only one computer.

In how many ways can he minimize the total length of the cables? Compute the answer modulo 10^9+7.

Constraints

  • 1 ≤ N ≤ 10^5
  • 0 ≤ a_i, b_i ≤ 10^9
  • The coordinates are integers.
  • The coordinates are pairwise distinct.

Input

The input is given from Standard Input in the following format:

N
a_1
:
a_N
b_1
:
b_N

Output

Print the number of ways to minimize the total length of the cables, modulo 10^9+7.

Examples

Input

2
0
10
20
30

Output

2

Input

3
3
10
8
7
12
5

Output

1

输入格式

见题面

输出格式

见题面

样例输入
2 0 10 20 30
样例输出
2