s = int(eval(input()))

list = [int(n) for n in input().split()]



print((sorted(list)[s//2] - sorted(list)[s//2 - 1]))

s = int(eval(input()))

list = [int(n) for n in input().split()]



s_l = sorted(list)

print((s_l[s//2] - s_l[s//2 - 1]))

s = int(eval(input()))
list = [int(n) for n in input().split()]
print((sorted(list)[s // 2] - sorted(list)[s // 2 - 1]))

s = int(eval(input()))
list = [int(n) for n in input().split()]
s_l = sorted(list)
print((s_l[s // 2] - s_l[s // 2 - 1]))

-print((sorted(list)[s // 2] - sorted(list)[s // 2 - 1])) +s_l = sorted(list) +print((s_l[s // 2] - s_l[s // 2 - 1]))