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#F2511. Permutation Sum

    ID: 2517 传统题 2000ms 256MiB 尝试: 0 已通过: 0 难度: 6 上传者: 标签>位运算组合数学动态规划模拟折半搜索数学编程与模拟搜索提高难度共享题库Codeforces英文题面题目来源题面语言

Permutation Sum

题目描述

D. Permutation Sum
time limit per test
3 seconds
memory limit per test
256 megabytes
input
standard input
output
standard output

Permutation p is an ordered set of integers p1,p2,...,pn, consisting of n distinct positive integers, each of them doesn't exceed n. We'll denote the i-th element of permutation p as pi. We'll call number n the size or the length of permutation p1,p2,...,pn.

Petya decided to introduce the sum operation on the set of permutations of length n. Let's assume that we are given two permutations of length n: a1,a2,...,an and b1,b2,...,bn. Petya calls the sum of permutations a and b such permutation c of length n, where ci=((ai-1+bi-1) mod n)+1 (1≤in).

Operation means taking the remainder after dividing number x by number y.

Obviously, not for all permutations a and b exists permutation c that is sum of a and b. That's why Petya got sad and asked you to do the following: given n, count the number of such pairs of permutations a and b of length n, that exists permutation c that is sum of a and b. The pair of permutations x,y (xy) and the pair of permutations y,x are considered distinct pairs.

As the answer can be rather large, print the remainder after dividing it by 1000000007 (109+7).

Input

The single line contains integer n (1≤n≤16).

Output

In the single line print a single non-negative integer − the number of such pairs of permutations a and b, that exists permutation c that is sum of a and b, modulo 1000000007 (109+7).

Examples
Input
3
Output
18
Input
5
Output
1800

题目来源:fps-www.educg.net-codeforce-1-2833.xml.zip;FPS 共享题包,题包内第 2153 题。保留原作者与原赛事署名。