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

#include <bits/stdc++.h>
using namespace std;
vector<long long> mint, maxt;
vector<long long> dp;
void build(long long v, long long l, long long r) {
  if (l + 1 == r) {
    mint[v] = maxt[v] = dp[l];
    return;
  }
  long long m = (r + l) / 2;
  build(2 * v + 1, l, m);
  build(2 * v + 2, m, r);
  mint[v] = min(mint[2 * v + 1], mint[2 * v + 2]);
  maxt[v] = max(maxt[2 * v + 1], maxt[2 * v + 2]);
}
long long maxi(long long v, long long l, long long r, long long L,
               long long R) {
  if (l >= L && r <= R) {
    return maxt[v];
  }
  if (l >= R || r <= L) {
    return -1e18;
  }
  long long m = (r + l) / 2;
  return max(maxi(2 * v + 1, l, m, L, R), maxi(2 * v + 2, m, r, L, R));
}
long long mini(long long v, long long l, long long r, long long L,
               long long R) {
  if (l >= L && r <= R) {
    return mint[v];
  }
  if (l >= R || r <= L) {
    return 1e18;
  }
  long long m = (r + l) / 2;
  return min(mini(2 * v + 1, l, m, L, R), mini(2 * v + 2, m, r, L, R));
}
signed main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cout.tie(NULL);
  long long n;
  cin >> n;
  vector<long long> p(n);
  for (auto &x : p) {
    cin >> x;
  }
  dp.assign(n + 1, 0);
  for (int i = 0; i < n; i++) {
    dp[i + 1] = dp[i] + p[i];
  }
  mint.resize(4 * (dp.size()));
  maxt.resize(4 * (dp.size()));
  build(0, 0, dp.size());
  vector<map<long long, long long> > left(n + 1), right(n + 1);
  map<long long, long long> last;
  for (int i = -30; i <= 30; i++) {
    last[i] = -1;
  }
  for (int i = 0; i < n; i++) {
    left[i + 1] = last;
    last[p[i]] = i + 1;
  }
  for (int i = -30; i <= 30; i++) {
    last[i] = dp.size();
  }
  for (int i = n - 1; i >= 0; i--) {
    right[i + 1] = last;
    last[p[i]] = i + 1;
  }
  long long ans = 0;
  for (int i = 0; i < n; i++) {
    long long l = -1;
    for (int j = p[i] + 1; j <= 30; j++) {
      l = max(l, left[i + 1][j]);
    }
    long long r = dp.size();
    for (int j = p[i] + 1; j <= 30; j++) {
      r = min(r, right[i + 1][j]);
    }
    long long maxx = maxi(0, 0, dp.size(), i + 1, r);
    long long minn = mini(0, 0, dp.size(), l + 1, i + 1);
    ans = max(ans, maxx - minn - p[i]);
  }
  cout << ans;
  return 0;
}
