# 端は寄与が1


def f(x, y):
    if x < 0 and y < 0:
        return -x - y
    return abs(x - y)


n = int(input())
a = list(map(int, input().split()))

pos = []
neg = []

for v in a:
    if v > 0:
        pos.append(v)
    else:
        neg.append(v)

pos.sort(reverse=True)
neg.sort(reverse=True)
arr = pos + neg
ans = 0
for i in range(1, n):
    ans += f(arr[i - 1], arr[i])

print(ans)