Given an n x n matrix, where every row and column is sorted in non-decreasing order. Find the kth smallest element in the given 2D array.Your task is to complete the function kthSmallest which takes two arguments the first is a matrix (mat) and sec argument is the order of the matrix (n) and the function returns the kth smallest element in the matrix.

For example, consider the following 2D array.
        10, 20, 30, 40
        15, 25, 35, 45
        24, 29, 37, 48
        32, 33, 39, 50
The 3rd smallest element is 20 and 7th smallest element is 30

Input:
The first line of input is an integer T denoting the no of test cases . Then T lines follow . The first line of each test case contains an integer N denoting the size of the matrix then in the next line are N*N space separated values of the matrix . The third line contains an integer k.

Output:
For each test case print in a new line the kth smallest element of the matrix  .

Constraints:
1<=T<=100
1<= N<=20
1<= M[][]<=100

Example
Input
1
4
16 28 60 64 22 41 63 91 27 50 87 93 36 78 87 94 
3
Output
27


Note:The Input/Ouput format and Example given are used for system's internal purpose, and should be used by a user for Expected Output only. As it is a function problem, hence a user should not read any input from stdin/console. The task is to complete the function specified, and not to write the full code.

** For More Input/Output Examples Use 'Expected Output' option **