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

l.sort()
ck1 = 0
if len(l) % 2 == 0:
    ck = len(l) // 2
    ck1 = ck - 1
else:
    ck = (len(l)+1) // 2

ck = l[ck-1]
ck1 = l[max(ck1-1,0)]


ans = 0
ans1 = 0

for li in l:
    ans += abs(ck - li)
    ans1 += abs(ck1 - li)

print(min(ans, ans1))