JJ loves playing with medians. He has an array A of length N (N is odd). He wants to partition the array A into two non-empty subsets P and Q such that the value of |median(P) - median(Q)| is as small as possible. (Note that each A_{i} must belong to either subset P or subset Q).

Help him find this minimum value of |median(P) - median(Q)|.

As a reminder, the median of a subset X of size N is the element which occupies the $\lfloor\frac{N+1}{2}\rfloor^{th}$ position after we sort the elements in non-decreasing order. For example$, median([3, 1, 4]) = 3, median([3, 1, 4, 2]) = 2. (Here \lfloor x \rfloor$ denotes the largest integer which does not exceed x).

------ Input Format ------

• The first line contains T - the number of test cases. Then the test cases follow.
• The first line of each test case contains an integer N - the size of the array A.
• The second line of each test case contains $N space separated integers A_{1}, A_{2}, \dots, A_{N}$ denoting the array A.

------ Output Format ------

Output the minimum value of |median(P) - median(Q)|.

------ Constraints ------

$1 ≤ T ≤ 100$
$3 ≤ N ≤ 999$
$1 ≤ A_{i} ≤ 10^{9}$
$N$ is odd.

----- Sample Input 1 ------
3
5
2 7 4 8 2
3
1 2 3
5
1 1 1 1 1

----- Sample Output 1 ------
2
1
0
----- explanation 1 ------
- Test case $1$: We can divide the array into following two subsets: $P = [2, 8], Q = [7, 4, 2]$, which has $|median(P) - median(Q)| = |2 - 4| = 2$. It can be proven that the answer can not be improved further.
- Test case $2$: We can divide the array into following two subsets: $P = [1, 3], Q = [2]$, which has $|median(P) - median(Q)| = |1 - 2| = 1$. It can be proven that the answer can not be improved further.
- Test case $3$: Observe that, for any partition of the array into any two non-empty subsets, the median of both the subsets will be $1$. Therefore the answer is $|1 - 1| = 0$.

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