Resli is a contestant, judge, system and administrator. He can do literally everything, but can he come up with good problems? Here is Resli's problem for you.
We define an index $$$i$$$ of some permutation $$$P$$$ to be a Resli-utiful index if it holds that $$$P_i \gt P_{i + 1}$$$.
You will be building a permutation $$$P$$$ of length $$$N$$$. You will be given a set $$$S$$$ of $$$K$$$ distinct integers, that represents some specific indices of permutation $$$P$$$.
You need to count the number of permutations $$$P$$$ of length $$$N$$$, such that for every Resli-utiful index $$$i$$$ of $$$P$$$, it holds that:
Find the answer, and print it modulo $$$10^9 + 7$$$.
The first line of input contains a single integer $$$T$$$ $$$(1 \le T \le 1000)$$$ — the number of testcases. Each testcase contains two lines.
The first line of each testcase contains two integers $$$N$$$ and $$$K$$$ $$$(2 \le N \le 2\cdot 10^5$$$, $$$1 \le K \lt N)$$$.
The second line of each testcase contains $$$K$$$ space-separated integers $$$S_1, S_2, \dots, S_K$$$ $$$(1 \le S_i \lt N)$$$ — the specific indices of $$$P$$$.
It's guaranteed that the sum of $$$K$$$ over all testcases does not exceed $$$2\cdot 10^5$$$
For each testcase print a single integer — the number of permutations $$$P$$$ that satisfy the condition, modulo $$$10^9+7$$$.
32 113 21 23 12
2 6 3
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