def solve():
    input()
    A = list(map(int, input().split()))

    A.sort()

    l = len(A)

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



if __name__ == '__main__':
    solve()