N = int(input())
P = list(map(int, input().split()))
D = dict()
for i in range(N):
    D[P[i]] = i + 1
ans = 0
start = N * (N + 1)//2
for i in range(N, 0, -1):
    ans = max(ans, start - 2 * D[i])
    start -= D[i]
print(ans)