# N,M,K=map(int, input().split())
# D=[[] for i in range(N)]
# for i in range(M):
#   a,b,d=map(int, input().split())
#   a-=1;b-=1
#   D[a].append((d,b));D[b].append((d,a))

N=int(input())
A=list(map(int, input().split()))
A=sorted(A)[::-1]
x,y=0,-1;f,s=0,0
for i in range(N):
  if i%2==0:
    f+=A[x]
    x+=1 
  else:
    s+=A[y]
    y-=1 
print(f+s)