#D7069. 1D Matching
1D Matching
1D Matching
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
inputFormat
Input
The input is given from Standard Input in the following format:
N a_1 : a_N b_1 : b_N
outputFormat
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
样例
2
0
10
20
30
2