import sys
from heapq import heapify, heappush, heappop
input = lambda: sys.stdin.readline().rstrip()

#  -----------------------  #

n = int(input())
hq = list(map(int, input().split()))
heapify(hq)

ans = 0
for _ in range(n):
  ans += heappop(hq) * heappop(hq)
print(ans)