def findZigZagSequence(a, n): a.sort() mid = int((n + 1)/2) a[mid], a[n-1] = a[n-1], a[mid] st = mid + 1 ed = n - 1 while(st <= ed): a[st], a[ed] = a[ed], a[st] st = st + 1 ed = ed + 1 for i in range (n): if i == n-1: print(a[i]) else: print(a[i], end = ' ') return test_cases = int(input()) for cs in range (test_cases): n = int(input()) a = list(map(int, input().split())) findZigZagSequence(a, n)