7651번 - G-Avoiding Sequence 다국어

문제

Given a set of distinct integers S and an integer G, we call a sequence of integers a G-Avoiding Sequence if the following two conditions hold:

1. the sequence is a permutation of the elements of S; and
2. for any two consecutive elements A and B in the sequence, A − B is not divisible by G.

Compute the number of G-Avoiding Sequences modulo the prime 1,234,567,891.

입력

The input consists of several test cases. The first line of each test case contains two integers N (1 ≤ N ≤ 200), the size of S, and G (1 ≤ G ≤ 1,000). The next line will contain N integers, which are the elements of S and between 0 and 10⁶. Input is followed by a single line with N = G = 0, which should not be processed.

출력

For each test case, output a single line containing the number of G-Avoiding Sequences modulo the prime 1,234,567,891.

제한

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