N = int(input())
A = list(map(int, input().split()))
pos = [-1] * N
for i, a in enumerate(A):
    pos[a-1] = i + 1

ans = 0

tmp = N * (N + 1) // 2
for i in reversed(range(N)):
    p = pos[i]
    ans = max(ans, tmp - 2 * p)
    tmp -= p

print(ans)