n=int(input())
a=list(map(int,input().split()))
ans=-10**20

ca=a+[0]
for i in range(n):
  ca[i]+=ca[i-1]
q=[0]*n
l=0
for i in range(n):
  q[i]=ca[i]-l
  l=min(l,ca[i])
ql=q[:]
ca=a[::-1]+[0]
for i in range(n):
  ca[i]+=ca[i-1]
q=[0]*n
l=0
for i in range(n):
  q[i]=ca[i]-l
  l=min(l,ca[i])
qr=q[:]
qr=qr[::-1]
qr1=qr[:]
qr2=qr[:]
for i in range(n-1):
  qr1[i]=max(qr1[i],qr1[i+1])
  qr2[i]=min(qr2[i],qr2[i+1])
for i in range(n-1):
  ans=max(ans,ql[i]*qr1[i+1],ql[i]*qr2[i+1])

ca=a+[0]
for i in range(n):
  ca[i]+=ca[i-1]
q=[0]*n
l=0
for i in range(n):
  q[i]=ca[i]-l
  l=max(l,ca[i])
ql=q[:]
ca=a[::-1]+[0]
for i in range(n):
  ca[i]+=ca[i-1]
q=[0]*n
l=0
for i in range(n):
  q[i]=ca[i]-l
  l=min(l,ca[i])
qr=q[:]
qr=qr[::-1]
qr1=qr[:]
qr2=qr[:]
for i in range(n-1):
  qr1[i]=max(qr1[i],qr1[i+1])
  qr2[i]=min(qr2[i],qr2[i+1])
for i in range(n-1):
  ans=max(ans,ql[i]*qr1[i+1],ql[i]*qr2[i+1])

ca=a+[0]
for i in range(n):
  ca[i]+=ca[i-1]
q=[0]*n
l=0
for i in range(n):
  q[i]=ca[i]-l
  l=min(l,ca[i])
ql=q[:]
ca=a[::-1]+[0]
for i in range(n):
  ca[i]+=ca[i-1]
q=[0]*n
l=0
for i in range(n):
  q[i]=ca[i]-l
  l=max(l,ca[i])
qr=q[:]
qr=qr[::-1]
qr1=qr[:]
qr2=qr[:]
for i in range(n-1):
  qr1[i]=max(qr1[i],qr1[i+1])
  qr2[i]=min(qr2[i],qr2[i+1])
for i in range(n-1):
  ans=max(ans,ql[i]*qr1[i+1],ql[i]*qr2[i+1])

ca=a+[0]
for i in range(n):
  ca[i]+=ca[i-1]
q=[0]*n
l=0
for i in range(n):
  q[i]=ca[i]-l
  l=max(l,ca[i])
ql=q[:]
ca=a[::-1]+[0]
for i in range(n):
  ca[i]+=ca[i-1]
q=[0]*n
l=0
for i in range(n):
  q[i]=ca[i]-l
  l=max(l,ca[i])
qr=q[:]
qr=qr[::-1]
qr1=qr[:]
qr2=qr[:]
for i in range(n-1):
  qr1[i]=max(qr1[i],qr1[i+1])
  qr2[i]=min(qr2[i],qr2[i+1])
for i in range(n-1):
  ans=max(ans,ql[i]*qr1[i+1],ql[i]*qr2[i+1])

print(ans)