import java.util.*;
import java.lang.*;
import java.io.*;
import java.math.*;
public class Main {
public static void main (String[] args) throws java.lang.Exception {
Scanner kb = new Scanner(System.in);
int test_cases = kb.nextInt();
for(int cs = 1; cs <= test_cases; cs++){
int n = kb.nextInt();
int a[] = new int[n];
for(int i = 0; i < n; i++){
a[i] = kb.nextInt();
}
findZigZagSequence(a, n);
}
}
public static void findZigZagSequence(int [] a, int n){
Arrays.sort(a);
int mid = (n + 1)/2 - 1;
int temp = a[mid];
a[mid] = a[n - 1];
a[n - 1] = temp;
int st = mid + 1;
int ed = n - 2;
while(st <= ed){
temp = a[st];
a[st] = a[ed];
a[ed] = temp;
st = st + 1;
ed = ed - 1;
}
for(int i = 0; i < n; i++){
if(i > 0) System.out.print(" ");
System.out.print(a[i]);
}
System.out.println();
}
}
