import sys
input = sys.stdin.readline

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

S=[0]
for a in A:
    S.append(S[-1]+a)

MAX1=[-1<<60]*(N+1)
MIN1=[1<<60]*(N+1)


MAX2=[-1<<60]*N
MIN2=[1<<60]*N

for i in range(N+1):
    MAX1[i]=max(MAX1[i-1],MAX1[i])
    MAX1[i]=max(MAX1[i],S[i])

for i in range(N+1):
    MIN1[i]=min(MIN1[i-1],MIN1[i])
    MIN1[i]=min(MIN1[i],S[i])

for i in range(N):
    MAX2[i]=max(MAX2[i],MAX2[i-1])
    MAX2[i]=max(MAX2[i],S[i+1]-MIN1[i])

    MIN2[i]=min(MIN2[i],MIN2[i-1])
    MIN2[i]=min(MIN2[i],S[i+1]-MAX1[i])


B=list(reversed(A))

S2=[0]
for a in B:
    S2.append(S2[-1]+a)

MAX3=[-1<<60]*(N+1)
MIN3=[1<<60]*(N+1)

MAX4=[-1<<60]*N
MIN4=[1<<60]*N

for i in range(N+1):
    MAX3[i]=max(MAX3[i-1],MAX3[i])
    MAX3[i]=max(MAX3[i],S2[i])

for i in range(N+1):
    MIN3[i]=min(MIN3[i-1],MIN3[i])
    MIN3[i]=min(MIN3[i],S2[i])

for i in range(N):
    MAX4[i]=max(MAX4[i],MAX4[i-1])
    MAX4[i]=max(MAX4[i],S2[i+1]-MIN3[i])

    MIN4[i]=min(MIN4[i],MIN4[i-1])
    MIN4[i]=min(MIN4[i],S2[i+1]-MAX3[i])

MAX4.reverse()
MIN4.reverse()

ANS=-1<<63

for i in range(N-1):
    ANS=max(ANS,MAX2[i]*MAX4[i+1],MIN2[i]*MIN4[i+1])

print(ANS)