1824A · LuoTianyi and the Show

Problem: There are $n$ people taking part in a show about VOCALOID. They will sit in the row of seats, numbered $1$ to $m$ from left to right.

The $n$ people come and sit in order. Each person occupies a seat in one of three ways:

1. Sit in the seat next to the left of the leftmost person who is already sitting, or if seat $1$ is taken, then leave the show. If there is no one currently sitting, sit in seat $m$.
2. Sit in the seat next to the right of the rightmost person who is already sitting, or if seat $m$ is taken, then leave the show. If there is no one currently sitting, sit in seat $1$.
3. Sit in the seat numbered $x_i$. If this seat is taken, then leave the show.

Now you want to know what is the maximum number of people that can take a seat, if you can let people into the show in any order?

Input Format: Each test consists of multiple test cases. The first line contains a single integer $t$ ($1 \le t \le 10^4$) — the number of test cases. The description of test cases follows.

The first line of each test case contains two integers $n$ and $m$ ($1 \le n, m \le 10^5$) — the number of people and the number of seats.

The second line of each test case contains $n$ integers $x_1, x_2, \ldots, x_n$ ($-2 \le x_i \le m$, $x_i \ne 0$), the $i$-th of which describes the way in which the $i$-th person occupies a seat:

1. If $x_i=-1$, then $i$-th person takes the seat in the first way.
2. If $x_i=-2$, then $i$-th person takes the seat in the second way.
3. If $x_i > 0$, then the $i$-th person takes a seat in the third way, i.e. he wants to sit in the seat with the number $x_i$ or leave the show if it is occupied..

It is guaranteed that sum of $n$ and the sum of $m$ over all test cases don't exceed $10^5$.

Output Format: For each test case output a single integer — the maximum number of people who can occupy a seat.

Note: In the first test case, all the people want to occupy the $5$ seat, so only $1$ people can occupy the seat.

In the second test case, we can let people in order $1, 2, 3, 4$, then all but the last person can take a seat.

In the third test case, we can let people into the show in that order:

Let the third person in:

–––3–––

Let the fourth person in:

–––34––

Let the fifth person in:

–––345–

Let the first person in:

––1345–

Let the second person in:

–21345–

Thus, all $5$ people took seats.

In the fifth test case, we can let people into the show in this order:

Let the fourth person in:

––––4–

Let the third person in:

–––34–

Let the sixth person in, he'll leave the show because he takes the third seat the third way and has to sit in the $4$ seat, but it's already taken:

–––34–

Let the fifth person in:

––534–

Let the first person in:

–1534–

Let the second person in:

21534–

Thus, $5$ of people took seats.

In the seventh test case, we can let people into the show in this order:

Let the third person in:

3––––––

Let the fourth person in:

34–––––

Let the fifth person in:

345––––

Let the sixth person in:

3456–––

Let the first person in:

34561––

Let the second person in, he will leave the show because he occupies the first way, but the $1$ seat is taken:

34561––

Thus, $5$ people took seats.