import sys
input = sys.stdin.readline
N = int(input())
a = list(map(int, input().split()))

import heapq
hpush = heapq.heappush
hpop = heapq.heappop

h = []
for x in a: hpush(h, -x)
res = 0
for k in range(N):
  c = 1 << k
  while c > 0 and len(h):
    res += -hpop(h) * k
    c -= 1
print(res)