from collections import*
n,*a=map(int,open(0).read().split())
a.sort(key=abs)
last=[a.pop(),a.pop()]
a.sort()
q=[last.pop()]+sorted(a)+[last.pop()]
s=0
for i,j in zip(q,q[1:]):
  if i<0 and j<0:
    s-=i+j
  else:
    s+=abs(i-j)
print(s)