"""

"""

import sys
from sys import stdin

N = int(stdin.readline())
c = list(map(int,stdin.readline().split()))
c.sort()


#aが最小を狙う
a = 0
b = 0
for i in range(N):
    if i % 2 == 0:
        a += c[i]
    else:
        b += c[i]
ans1 = abs(a)-abs(b)
print (a,b,file=sys.stderr)

a = sum(c[:(N+1)//2])
b = sum(c[(N+1)//2:])
ans = min(ans1 , abs(a)-abs(b))
print (a,b,file=sys.stderr)

#aが最大を狙う
c.reverse()
a = 0
b = 0
for i in range(N):
    if i % 2 == 0:
        a += c[i]
    else:
        b += c[i]
ans2 = abs(a)-abs(b)
print (a,b,file=sys.stderr)

a = sum(c[:(N+1)//2])
b = sum(c[(N+1)//2:])
ans = min(ans2 , abs(a)-abs(b))
print (a,b,file=sys.stderr)

print (max(ans1,ans2))