# from itertools import permutations

# n = 6
# kumiawase = list(permutations(range(1, n + 1), n))
# ans = 0
# goukei = n * (n + 1) // 2
# for kumi1 in kumiawase:
#     expected = n * (n + 1) // 2
#     for i in range(n):
#         if kumi1[i] == n:
#             expected -= 2 * (i + 1)
#         for kumi2 in kumiawase:
#             res = 0
#             for i in range(n):
#                 p = kumi1[i]
#                 k = kumi2[i]
#                 if k > p:
#                     res += i + 1
#                 elif p > k:
#                     res -= i + 1
#             if res > expected:
#                 print(kumi1, kumi2, res, expected)
#             ans = max(ans, res)
# print(ans)

n = int(input())
P = list(map(int, input().split()))

PP = [(p, i) for i, p in enumerate(P)]
PP.sort(reverse=True)
ans = 0
for idx, (p, i) in enumerate(PP):
    ans = max(ans, (n - idx - 1) * (n - idx) // 2 - (2 * i + 1))
print(max(0, ans))