mod = 1000000007
eps = 10**-9


def main():
    import sys
    input = sys.stdin.readline

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

    idx = {p: i+1 for i, p in enumerate(P)}
    ans = 0
    cur = N * (N+1) // 2
    for p in range(N, 0, -1):
        ans = max(ans, cur - idx[p] * 2)
        cur -= idx[p]
    print(ans)


if __name__ == '__main__':
    main()