import sys

# sys.setrecursionlimit(200005)
# sys.set_int_max_str_digits(200005)
int1 = lambda x: int(x)-1
pDB = lambda *x: print(*x, end="\n", file=sys.stderr)
p2D = lambda x: print(*x, sep="\n", end="\n\n", file=sys.stderr)
def II(): return int(sys.stdin.readline())
def LI(): return list(map(int, sys.stdin.readline().split()))
def LLI(rows_number): return [LI() for _ in range(rows_number)]
def LI1(): return list(map(int1, sys.stdin.readline().split()))
def LLI1(rows_number): return [LI1() for _ in range(rows_number)]
def SI(): return sys.stdin.readline().rstrip()

# dij = [(0, 1), (-1, 0), (0, -1), (1, 0)]
dij = [(0, 1), (-1, 0), (0, -1), (1, 0), (1, 1), (1, -1), (-1, 1), (-1, -1)]
# inf = -1-(-1 << 31)
inf = -1-(-1 << 62)

# md = 10**9+7
md = 998244353

def f(aa):
    mns=[inf]*(n+1)
    mxs=[-inf]*(n+1)
    s=0
    mn=mx=0
    for i,a in enumerate(aa):
        s+=a
        mns[i+1]=min(mns[i],s-mx)
        mxs[i+1]=max(mxs[i],s-mn)
        mx=max(mx,s)
        mn=min(mn,s)
    return mns,mxs

n=II()
aa=LI()
l,L=f(aa)
r,R=f(aa[::-1])
ans=-inf
for i in range(1,n):
    ans=max(ans,l[i]*r[n-i],L[i]*R[n-i])
print(ans)