Palindromic Substring Discovery

Given a string \(S\), find the largest substring \(W\) such that you can move the characters of \(W\) as you see fit and create a palindrome.

Input Format

\(T\) denoting the number of test cases.

For every \(T\) testcases, there is a single line with \(N\) denoting the length of string in this testcase and \(S\) string.

Output Format

Output \(T\) lines with a single digit each denoting the maximum length possible for \(W\)

Constraints

Sample Input 0

3
4 abcd
6 aabbcd
7 abcbcda

Sample Output 0

1
5
7