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


# バブルソートここから
def sortList_once(X):
    l = len(X)
    for i in range(l-1):
        n = X[i]
        m = X[i+1]
        if n>m:
            X[i] = m
            X[i+1] = n
    return X

n = N
while n>0:
    A = sortList_once(A)
    n -= 1
# バブルソートここまで


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