N = int(input())
A = [int(x) for x in input().split()]
A.sort()
half_n = N // 2
center_value = -1
if N % 2:
    center_value = A[half_n]
else:
    c1,c2 = A[half_n - 1:half_n + 1]
    center_value = (c1 + c2) / 2
if center_value % 1:
    center_value = "{:.1f}".format(center_value)
else:
    center_value = "{:.0f}".format(center_value)
print(center_value)