题面
Definition 1. n!!…! = n(n-k)(n-2k)…(n mod k), if k doesn’t divide n,
n!!…! = n(n-k)(n-2k)…k, if k divides n (There are k marks ! in the both cases).
Definition 2. X mod Y ― a remainder after division of X by Y.
For example, 10 mod 3 = 1; 3! = 3・2・1; 10!!! = 10・7・4・1;
Given numbers n and k we have calculated a value of the expression in the first definition. Can you do it as well?
输入格式
There are several test cases.Each contains the only line: one integer n, 1 ≤ n ≤ 10, then exactly one space, then k exclamation marks, 1 ≤ k ≤ 20.
输出格式
contains one number ― n!!…! (there are k marks ! here).
样例
输入
9 !!
输出
945