Tim is doing a test consisting of $$$4n$$$ questions; each question has $$$4$$$ options: 'A', 'B', 'C', and 'D'. For each option, there are exactly $$$n$$$ correct answers corresponding to that option — meaning there are $$$n$$$ questions with the answer 'A', $$$n$$$ questions with the answer 'B', $$$n$$$ questions with the answer 'C', and $$$n$$$ questions with the answer 'D'.

For each question, Tim wrote his answer on the answer sheet. If he could not figure out the answer, he would leave a question mark '?' for that question.

You are given his answer sheet of $$$4n$$$ characters. What is the maximum number of correct answers Tim can get?

Input format:
The first line contains a single integer $$$t$$$ ($$$1 \le t \le 1000$$$) — the number of test cases.

The first line of each test case contains an integer $$$n$$$ ($$$1 \le n \le 100$$$).

The second line of each test case contains a string $$$s$$$ of $$$4n$$$ characters ($$$s_i \in \{\texttt{A}, \texttt{B}, \texttt{C}, \texttt{D}, \texttt{?}\}$$$) — Tim's answers for the questions.
Output format:
For each test case, print a single integer — the maximum score that Tim can achieve.
Example Input 0:
6
1
ABCD
2
AAAAAAAA
2
AAAABBBB
2
????????
3
ABCABCABCABC
5
ACADC??ACAC?DCAABC?C

Example Output 0:
4
2
4
0
9
13

Notes:
In the first test case, there is exactly one question with each answer 'A', 'B', 'C', and 'D'; so it's possible that Tim gets all his answers correct.

In the second test case, there are only two correct answers 'A' which makes him get exactly $$$2$$$ points in any case.

In the third test case, Tim can get at most $$$2$$$ correct answers with option 'A' and $$$2$$$ correct answers with option 'B'. For example, he would get $$$4$$$ points if the answers were 'AACCBBDD'.

In the fourth test case, he refuses to answer any question at all, which makes him get $$$0$$$ points.

Example input:
6
1
ABCD
2
AAAAAAAA
2
AAAABBBB
2
????????
3
ABCABCABCABC
5
ACADC??ACAC?DCAABC?C


Example output:
4
2
4
0
9
13