N = int(input())
Y = [int(y) for y in input().split()]

Y.sort()
cnt = 0
prev = Y[0]-1
for y in Y:
    if y == prev:
        continue
    cnt += 1
    prev = y

if N%4 == 0 or N%4 == 3:
    a = (Y[N//4-1]+Y[N//4])//2
    b = (Y[3*N//4-1]+Y[3*N//4])//2
else:
    a = Y[N//4]
    b = Y[3*N//4]

ans = 0
for y in Y:
    ans += min(abs(y-a), abs(y-b))
if cnt == 1:
    ans = 1
elif cnt == 2:
    ans = 0
print(ans)