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

L=[A[0]] 
LL=[A[0]] 
for i in range(1,N):
  a=A[i]
  L.append((max(a,L[-1]+a)))
  LL.append((min(a,LL[-1]+a)))



B=A[::-1]
R=[B[0]] 
RR=[B[0]] 
for i in range(1,N):
  a=B[i]
  R.append((max(a,R[-1]+a)))
  RR.append((min(a,RR[-1]+a)))
R=R[::-1]
RR=RR[::-1]

for i in range(N-2,-1,-1):
  R[i]=max(R[i],R[i+1])
  RR[i]=min(RR[i],RR[i+1])


ans=-10**10
for i in range(N-1):
  ans=max(ans,L[i]*R[i+1],LL[i]*RR[i+1])
print(ans)