def bubble(x):
    for i in range(len(x)):
        for j in range(len(x) - 1):
            if x[j] < x[j+1]:
                x[j], x[j+1] = x[j+1], x[j]

    return x
        

N = int(input())
A = list(map(int, input().split()))

bubble(A)

if N % 2 == 0:
    print((A[int(N/2)] + A[int(N/2) - 1]) / 2)
else:
    print(A[int((N+1)/2) - 1])