N = int(input())
scores = map (int, raw_input().split())

if len(scores) % 2 == 1:
    while len(scores) > 1:
        scores.remove(max(scores))
        scores.remove(min(scores))
    median = scores[0]

else:
    while len(scores) > 2:
        scores.remove(max(scores))
        scores.remove(min(scores))
    median = sum(scores)/2.0

print median