You are given a string of length of lowercase letters. You are allowed to choose an index and replace with a different lowercase letter at most once. Determine the longest substring of identical characters in the string after replacing a character at most once.

#### Constraints

The sum of over all test cases does not exceed .

#### Input Specification

The first line contains a single integer , representing the number of test cases.

For each test case, there are two lines:

The first line contains a single integer .

The second line contains a string of length .

#### Output Specification

For each test case, output a single integer: the length of the longest substring of identical characters in after replacing a character at most once.

#### Sample Input

```
3
3
abc
4
aaab
4
baaa
```

#### Sample Output

```
2
4
4
```

#### Sample Explanation

For the first test case, changing any character to match one of its neighbors yields a substring of length with identical characters.

In the second test case, changing the last character to `a`

yields `aaaa`

as a substring with identical characters.

In the third test case, changing the first character to `a`

also yields `aaaa`

as a substring.

## Comments