Finally, a COVID vaccine is out on the market and the Chefland government has asked you to form a plan to distribute it to the public as soon as possible. There are a total of $N$ people with ages $a_1, a_2, \ldots, a_N$.
There is only one hospital where vaccination is done and it is only possible to vaccinate up to $D$ people per day. Anyone whose age is $\ge 80$ or $\le 9$ is considered to be at risk. On each day, you may not vaccinate both a person who is at risk and a person who is not at risk. Find the smallest number of days needed to vaccinate everyone.

-----Input-----
- The first line of the input contains a single integer $T$ denoting the number of test cases. The description of $T$ test cases follows.
- The first line of each test case contains two space-separated integers $N$ and $D$.
- The second line contains $N$ space-separated integers $a_1, a_2, \ldots, a_N$.

-----Output-----
For each test case, print a single line containing one integer ― the smallest required number of days.

-----Constraints-----
- $1 \le T \le 10$
- $1 \le N \le 10^4$
- $1 \le D \le 10^5$
- $1 \le a_i \le 100$ for each valid $i$

-----Subtasks-----
Subtask #1 (100 points): original constraints

-----Example Input-----
2
10 1
10 20 30 40 50 60 90 80 100 1
5 2
9 80 27 72 79

-----Example Output-----
10
3

-----Explanation-----
Example case 1: We do not need to worry about how the people are grouped, since only one person can be vaccinated in a single day. We require as many days as there are people.
Example case 2: There are two people at risk and three people who are not at risk. One optimal strategy is to vaccinate the two people at risk on day $1$ and the remaining three on the next $2$ days.

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