10
-3 4 -4 1 1 -4 -5 3 -4 -2
 10
8 9 -10 -10 -4 -3 5 9 -9 9
 6
5 -4 2 -1 2 -2
 11
3 0 1 -2 5 -5 -1 0 3 2 2
 10
4 -2 -2 -2 2 0 1 0 -4 -1
 4
2 2 -3 4
 11
-11 -7 -2 -24 30 -26 24 9 -8 -9 23
 6
30 -29 5 5 -29 30
 24
-8 -6 6 -11 -15 -7 10 -19 -6 21 14 -4 -21 -10 12 17 1 -1 5 19 2 0 -4 -23
 10
-9 -6 -1 9 -2 0 0 -1 5 0
 6
10 -8 3 3 -8 10
 10
-2 -3 -1 4 -3 2 0 1 -5 4
 5
30 -29 10 -1 10
 31
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 -29 30
 7
30 -20 5 1 3 -20 30
 5
30 -29 4 -3 4
 10
-5 28 -18 -10 9 -2 11 -6 -19 30
 8
4 -10 13 -13 2 2 -11 6
 131
30 -29 29 -28 28 -28 28 -28 28 -28 28 -28 28 -28 28 -28 28 -28 28 -28 28 -28 28 -28 28 -28 28 -28 28 -28 28 -28 28 -28 28 -28 28 -28 28 -28 28 -28 28 -28 28 -28 28 -28 28 -28 28 -28 28 -28 28 -28 28 -28 28 -28 28 -28 28 -28 28 -28 28 -28 28 -28 28 -28 28 -28 28 -28 28 -28 28 -28 28 -28 28 -28 28 -28 28 -28 28 -28 28 -28 28 -28 28 -28 28 -28 28 -28 28 -28 28 -28 28 -28 28 -28 28 -28 28 -28 28 -28 28 -28 28 -28 28 -28 28 -28 28 -28 28 -28 28 -28 27 -26 27
 10
-4 4 0 -2 3 0 1 2 3 -4
 10
-2 -8 5 4 -1 -6 -9 6 1 -6
 7
25 -17 13 13 -25 25 -24
 10
3 -3 2 1 -4 -2 3 -2 -3 0
 10
4 -5 0 4 0 0 -3 1 1 -4
 10
0 4 4 1 -3 4 2 1 4 -1
 17
15 -13 7 8 8 1 -19 12 8 -23 -4 16 -13 -28 10 -30 -14
 4
1 1 -4 10
 11
3 -2 1 1 1 1 1 1 1 -3 4
 7
30 -29 10 10 10 -29 30
 7
25 -13 17 -23 12 12 9
 7
15 -14 10 10 10 -14 15
 10
3 0 0 -4 3 1 -2 -1 -1 4
 6
8 -7 7 -6 5 5
 10
1 -4 -4 4 -2 -3 3 0 -2 3
 15
1 -26 -6 26 7 10 -2 -4 -6 14 -9 25 9 -12 -28
 6
30 -29 10 10 -29 30
 1
6
 2
1 1
 5
0 5 -4 3 -1
 7
5 -4 3 -1 3 -4 4
 10
16 -15 13 -1 10 -2 -20 26 5 -30
 10
-1 2 0 -1 2 -1 4 3 -5 1
 7
5 -4 1 1 1 -4 5
 5
10 -3 -5 3 5
 10
4 -4 3 -2 3 -4 -2 0 1 0
 10
-5 -5 -3 1 -2 2 0 2 -3 4
 10
2 -4 -2 3 1 1 -2 -1 -3 4
 10
-4 -5 4 -3 2 -2 2 1 -1 0
 10
0 -1 4 -2 3 -2 -1 -5 -5 2
 5
19 -6 1 -11 19
 10
1 0 -4 3 -5 3 -1 2 2 -5
 7
5 -5 3 4 3 -5 5
 10
-5 2 -3 -3 -4 3 3 0 2 4
 4
2 3 -10 11
 10
27 -17 15 -22 18 17 -6 2 16 -14
 6
30 -22 6 7 -22 30
 7
30 -25 0 6 9 -2 10
 9
7 2 -1 1 1 -10 6 -1 6
 4
1 -10 1 10
 5
17 -16 12 -11 15
 35
-23 -22 23 4 -22 29 -4 -6 -28 18 -5 21 -7 -8 -11 -7 30 -25 -1 12 19 5 -8 12 -1 10 -24 -19 24 -17 -7 24 20 -22 16
 10
4 -3 1 -2 1 1 0 -4 4 -2
 10
4 -2 1 0 1 -5 -2 1 0 -5
 2
3 9
 9
11 -5 -5 1 2 3 -5 -5 11

1
 8
 1
 4
 1
 2
 15
 5
 36
 2
 3
 1
 9
 28
 4
 1
 7
 2
 1
 7
 4
 13
 1
 1
 13
 16
 1
 6
 20
 21
 20
 1
 5
 1
 44
 10
 0
 1
 0
 2
 9
 5
 2
 3
 1
 2
 2
 1
 1
 3
 3
 6
 8
 2
 29
 6
 13
 5
 1
 1
 30
 1
 1
 3
 3

from itertools import accumulate
import sys;input=sys.stdin.readline
class SegTree:
    def __init__(self, init_val, n, ide_ele, seg_func):
        self.segfunc = seg_func
        self.num = 2**(n-1).bit_length()
        self.ide_ele = ide_ele
        self.seg=[self.ide_ele]*2*self.num
        for i in range(n):
            self.seg[i+self.num-1]=init_val[i]    
        for i in range(self.num-2,-1,-1) :
            self.seg[i]=self.segfunc(self.seg[2*i+1],self.seg[2*i+2]) 
        
    def update(self, k, x):
        k += self.num-1
        self.seg[k] = x
        # k+1ではなくkでは？
        while k+1:
            k = (k-1)//2
            self.seg[k] = self.segfunc(self.seg[k*2+1],self.seg[k*2+2])
        
    def query(self, p, q):
        if q<=p:
            return self.ide_ele
        p += self.num-1
        q += self.num-2
        res=self.ide_ele
        while q-p>1:
            if p&1 == 0:
                res = self.segfunc(res,self.seg[p])
            if q&1 == 1:
                res = self.segfunc(res,self.seg[q])
                q -= 1
            p = p//2
            q = (q-1)//2
        if p == q:
            res = self.segfunc(res,self.seg[p])
        else:
            res = self.segfunc(self.segfunc(res,self.seg[p]),self.seg[q])
        return res

n = int(input())
xs = [0] + list(map(int, input().split()))
X = list(accumulate(xs))

xis = [(i, x) for i, x in enumerate(xs)]
xis = sorted(xis, key=lambda x:x[1])[::-1]
bx = None
tmp = []
F = [(0, n+1)]*(n+1)
sti1 = SegTree([0]*(n+1), n+1, -1, max)
sti2 = SegTree([n+1]*(n+1), n+1, 10**18, min)
for i, x in xis:
#    print(bx, x)
    if bx == x:
        pass
    else:
        for j in tmp:
            sti1.update(j, j)
            sti2.update(j, j)
        tmp = []
    F[i] = (sti1.query(0, i), sti2.query(i, n+1))
    tmp.append(i)
    bx = x
#print(F)

st1 = SegTree(X, n+1, -10000, max)
st2 = SegTree(X, n+1, 10**18, min)
#print(X, n)
R = 0
for i in range(1, n+1):
    k, l = F[i]
#    print(i, st1.query(3, 8),st2.query(k, i-1),xs[i])
    R = max(R, st1.query(i, l)-st2.query(k, i-1)-xs[i])
print(R)
    
