from sys import stdin,setrecursionlimit#,set_int_max_str_digits
#import pypyjit
#pypyjit.set_param('max_unroll_recursion=-1')
setrecursionlimit(20000000) # これこどふぉだと無理
#set_int_max_str_digits(200010)
mod = 998244353 
ii = lambda :int(stdin.readline())
mi = lambda :map(int,stdin.readline().split())
li = lambda :list(mi())
gmi = lambda :map(lambda x: int(x) - 1, stdin.readline().split())
gi = lambda :list(map(lambda x: 0 if x == "." else 1,input())) # グリッド入力受け取り
py = lambda :print("Yes")
pn = lambda :print("No")
pf = lambda :print("First") 
ps = lambda :print("Second")
vec = [(1,0),(-1,0),(0,-1),(0,1)]
vec1 = [(1,0),(1,1),(0,1),(-1,1),(-1,0),(-1,-1),(0,-1),(1,-1)] #8方向
inf = 2*10**18


n = ii() 
a = li() 

def solve(a):
    mae = [0]*(n)
    now = 0 
    tmp = 0 
    for i in range(n):
        now += a[i] 
        mae[i] = now-tmp 
        if i:
            mae[i] = max(mae[i],mae[i-1])
        tmp = min(tmp,now)

    usiro = [0]*n 
    now = 0 
    tmp = 0 
    for i in range(n):
        now += a[-i-1]
        usiro[-i-1] = now-tmp 
        if i:
            usiro[-i-1] = max(usiro[-i-1],usiro[-i])
        tmp = min(tmp,now)

    ret = -inf
    for i in range(n-1):
        ret = max(ret,mae[i]*usiro[i+1])
    
    return ret

now = solve(a)

for i in range(n):
    a[i] *= -1 

now = max(now,solve(a))

print(now)