Problem C. Great Sequence

时间限制 1 ms   内存限制 256 MB

A sequence of positive integers is called great for a positive integer $$$x$$$, if we can split it into pairs in such a way that in each pair the first number multiplied by $$$x$$$ is equal to the second number. More formally, a sequence $$$a$$$ of size $$$n$$$ is great for a positive integer $$$x$$$, if $$$n$$$ is even and there exists a permutation $$$p$$$ of size $$$n$$$, such that for each $$$i$$$ ($$$1 \le i \le \frac{n}{2}$$$) $$$a_{p_{2i-1}} \cdot x = a_{p_{2i}}$$$.

Sam has a sequence $$$a$$$ and a positive integer $$$x$$$. Help him to make the sequence great: find the minimum possible number of positive integers that should be added to the sequence $$$a$$$ to make it great for the number $$$x$$$.

输入数据

Each test contains multiple test cases. The first line contains a single integer $$$t$$$ ($$$1 \le t \le 20\,000$$$) — the number of test cases. Description of the test cases follows.

The first line of each test case contains two integers $$$n$$$, $$$x$$$ ($$$1 \le n \le 2 \cdot 10^5$$$, $$$2 \le x \le 10^6$$$).

The next line contains $$$n$$$ integers $$$a_1, a_2, \ldots, a_n$$$ ($$$1 \le a_i \le 10^9$$$).

It is guaranteed that the sum of $$$n$$$ over all test cases does not exceed $$$2 \cdot 10^5$$$.

输出数据

For each test case print a single integer — the minimum number of integers that can be added to the end of $$$a$$$ to make it a great sequence for the number $$$x$$$.

样例

样例说明

In the first test case, Sam got lucky and the sequence is already great for the number $$$4$$$ because you can divide it into such pairs: $$$(1, 4)$$$, $$$(4, 16)$$$. Thus we can add $$$0$$$ numbers.

In the second test case, you can add numbers $$$1$$$ and $$$14$$$ to the sequence, then you can divide all $$$8$$$ integers into such pairs: $$$(1, 2)$$$, $$$(1, 2)$$$, $$$(2, 4)$$$, $$$(7, 14)$$$. It is impossible to add less than $$$2$$$ integers to fix the sequence.

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