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

import java.util.*;
import java.io.*;

public class Main {

    static long startTime = System.currentTimeMillis();

    // for global initializations and methods starts here

    // global initialisations and methods end here

    static void run() {
        boolean tc = false;
        AdityaFastIO r = new AdityaFastIO();
        //FastReader r = new FastReader();

        try (OutputStream out = new BufferedOutputStream(System.out)) {

            //long startTime = System.currentTimeMillis();

            int testcases = tc ? r.ni() : 1;
            int tcCounter = 1;
            // Hold Here Sparky------------------->>>
            // Solution Starts Here

            start:
            while (testcases-- > 0) {

                int n = r.ni();

                int[] arr = new int[n + 1];
                for (int i = 1; i <= n; i++) arr[i] = r.ni();

                int maxe1 = 100010;
                int maxe2 = 61;
                int[][] dpL = new int[maxe1][maxe2];
                int[][] dpR = new int[maxe1][maxe2];

                for (int i = 1; i <= n; i++) {
                    int ele = arr[i] + 30;
                    for (int j = ele; j <= 60; j++) {
                        dpL[i][j] = Math.max(0, dpL[i - 1][j] + ele - 30);
                    }
                }

                for (int i = n; i > 0; i--) {
                    int ele = arr[i] + 30;
                    for (int j = ele; j <= 60; j++) {
                        dpR[i][j] = Math.max(0, dpR[i + 1][j] + ele - 30);
                    }
                }

                int ans = 0;
                for (int i = 1; i <= n; i++) {
                    int left = dpL[i - 1][arr[i] + 30];
                    int right = dpR[i + 1][arr[i] + 30];
                    ans = Math.max(ans, left + right);
                }

                out.write((ans + " ").getBytes());


            }
            // Solution Ends Here
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    static class AdityaFastIO {
        final private int BUFFER_SIZE = 1 << 16;
        private final DataInputStream din;
        private final byte[] buffer;
        private int bufferPointer, bytesRead;
        public BufferedReader br;
        public StringTokenizer st;

        public AdityaFastIO() {
            br = new BufferedReader(new InputStreamReader(System.in));
            din = new DataInputStream(System.in);
            buffer = new byte[BUFFER_SIZE];
            bufferPointer = bytesRead = 0;
        }

        public AdityaFastIO(String file_name) throws IOException {
            din = new DataInputStream(new FileInputStream(file_name));
            buffer = new byte[BUFFER_SIZE];
            bufferPointer = bytesRead = 0;
        }

        public String word() {
            while (st == null || !st.hasMoreElements()) {
                try {
                    st = new StringTokenizer(br.readLine());
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            return st.nextToken();
        }

        public String line() {
            String str = "";
            try {
                str = br.readLine();
            } catch (IOException e) {
                e.printStackTrace();
            }
            return str;
        }

        public String readLine() throws IOException {
            byte[] buf = new byte[100000001]; // line length
            int cnt = 0, c;
            while ((c = read()) != -1) {
                if (c == '\n') break;
                buf[cnt++] = (byte) c;
            }
            return new String(buf, 0, cnt);
        }

        public int ni() throws IOException {
            int ret = 0;
            byte c = read();
            while (c <= ' ') c = read();
            boolean neg = (c == '-');
            if (neg) c = read();
            do {
                ret = ret * 10 + c - '0';
            }
            while ((c = read()) >= '0' && c <= '9');
            if (neg) return -ret;
            return ret;
        }

        public long nl() throws IOException {
            long ret = 0;
            byte c = read();
            while (c <= ' ') c = read();
            boolean neg = (c == '-');
            if (neg) c = read();
            do {
                ret = ret * 10 + c - '0';
            }
            while ((c = read()) >= '0' && c <= '9');
            if (neg) return -ret;
            return ret;
        }

        public double nd() throws IOException {
            double ret = 0, div = 1;
            byte c = read();
            while (c <= ' ') c = read();
            boolean neg = (c == '-');
            if (neg) c = read();
            do {
                ret = ret * 10 + c - '0';
            }
            while ((c = read()) >= '0' && c <= '9');
            if (c == '.') while ((c = read()) >= '0' && c <= '9') ret += (c - '0') / (div *= 10);
            if (neg) return -ret;
            return ret;
        }

        private void fillBuffer() throws IOException {
            bytesRead = din.read(buffer, bufferPointer = 0, BUFFER_SIZE);
            if (bytesRead == -1) buffer[0] = -1;
        }

        private byte read() throws IOException {
            if (bufferPointer == bytesRead) fillBuffer();
            return buffer[bufferPointer++];
        }

        public void close() throws IOException {
            if (din == null) return;
            din.close();
        }
    }

    public static void main(String[] args) throws Exception {
        run();
    }

    static long mod = 998244353;

    static long modInv(long base, long e) {
        long result = 1;
        base %= mod;
        while (e > 0) {
            if ((e & 1) > 0) result = result * base % mod;
            base = base * base % mod;
            e >>= 1;
        }
        return result;
    }

    static class FastReader {
        BufferedReader br;
        StringTokenizer st;

        public FastReader() {
            br = new BufferedReader(new InputStreamReader(System.in));
        }

        String word() {
            while (st == null || !st.hasMoreElements()) {
                try {
                    st = new StringTokenizer(br.readLine());
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            return st.nextToken();
        }

        String line() {
            String str = "";
            try {
                str = br.readLine();
            } catch (IOException e) {
                e.printStackTrace();
            }
            return str;
        }

        int ni() {
            return Integer.parseInt(word());
        }

        long nl() {
            return Long.parseLong(word());
        }

        double nd() {
            return Double.parseDouble(word());
        }
    }

    static int MOD = (int) (1e9 + 7);

    static long powerLL(long x, long n) {
        long result = 1;
        while (n > 0) {
            if (n % 2 == 1) result = result * x % MOD;
            n = n / 2;
            x = x * x % MOD;
        }
        return result;
    }

    static long powerStrings(int i1, int i2) {
        String sa = String.valueOf(i1);
        String sb = String.valueOf(i2);
        long a = 0, b = 0;
        for (int i = 0; i < sa.length(); i++) a = (a * 10 + (sa.charAt(i) - '0')) % MOD;
        for (int i = 0; i < sb.length(); i++) b = (b * 10 + (sb.charAt(i) - '0')) % (MOD - 1);
        return powerLL(a, b);
    }

    static long gcd(long a, long b) {
        if (a == 0) return b;
        else return gcd(b % a, a);
    }

    static long lcm(long a, long b) {
        return (a * b) / gcd(a, b);
    }

    static long lower_bound(List<Long> list, long k) {
        int s = 0;
        int e = list.size();
        while (s != e) {
            int mid = (s + e) >> 1;
            if (list.get(mid) < k) s = mid + 1;
            else e = mid;
        }
        if (s == list.size()) return -1;
        return s;
    }

    static int upper_bound(List<Long> list, long k) {
        int s = 0;
        int e = list.size();
        while (s != e) {
            int mid = (s + e) >> 1;
            if (list.get(mid) <= k) s = mid + 1;
            else e = mid;
        }
        if (s == list.size()) return -1;
        return s;
    }

    static void addEdge(ArrayList<ArrayList<Integer>> graph, int edge1, int edge2) {
        graph.get(edge1).add(edge2);
        graph.get(edge2).add(edge1);
    }

    public static class Pair implements Comparable<Pair> {
        int first;
        int second;

        public Pair(int first, int second) {
            this.first = first;
            this.second = second;
        }

        public String toString() {
            return "(" + first + "," + second + ")";
        }

        public int compareTo(Pair o) {
            // TODO Auto-generated method stub
            if (this.first != o.first)
                return (int) (this.first - o.first);
            else return (int) (this.second - o.second);
        }
    }

    public static class PairC<X, Y> implements Comparable<PairC> {
        X first;
        Y second;

        public PairC(X first, Y second) {
            this.first = first;
            this.second = second;
        }

        public String toString() {
            return "(" + first + "," + second + ")";
        }

        public int compareTo(PairC o) {
            // TODO Auto-generated method stub
            return o.compareTo((PairC) first);
        }
    }

    static boolean isCollectionsSorted(List<Long> list) {
        if (list.size() == 0 || list.size() == 1) return true;
        for (int i = 1; i < list.size(); i++) if (list.get(i) <= list.get(i - 1)) return false;
        return true;
    }

    static boolean isCollectionsSortedReverseOrder(List<Long> list) {
        if (list.size() == 0 || list.size() == 1) return true;
        for (int i = 1; i < list.size(); i++) if (list.get(i) >= list.get(i - 1)) return false;
        return true;
    }

}