import sys
input = sys.stdin.readline

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

P2=[(P[i],i+1) for i in range(N)]

P2.sort(reverse=True)

SUM=[0]

for x,y in P2[::-1]:
    SUM.append(SUM[-1]+y)

SUM.reverse()

ANS=0

for i in range(1,N):
    ANS=max(ANS,SUM[i]-P2[i-1][1])

print(ANS)