#! /Users/shogokobayashi/anaconda/bin/python

a = input()
numbers = list(map(int, input().split(' ')))
sorted_numbers = sorted(numbers)

if len(sorted_numbers) %2 != 0:
    print(sorted_numbers[len(sorted_numbers)//2])
else:
    print((sorted_numbers[int(len(sorted_numbers)//2)] + sorted_numbers[int(len(sorted_numbers)//2)-1])/2)