import java.io.BufferedWriter;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStreamWriter;
import java.util.InputMismatchException;

public class Q3 {

	public static void main(String[] args) throws Exception {
		Scan scn = new Scan();
		Print printer = new Print();

		int n = scn.scanInt();
		int[] arr = new int[n];

		for (int i = 0; i < arr.length; i++) {
			arr[i] = scn.scanInt();
		}
		maxSubArraySum(arr, n);

		printer.close();

	}

	public static void maxSubArraySum(int a[], int size) {
		int max_so_far = Integer.MIN_VALUE, max_ending_here = 0, start = 0, end = 0, s = 0;

		for (int i = 0; i < size; i++) {
			max_ending_here += a[i];

			if (max_so_far < max_ending_here) {
				max_so_far = max_ending_here;
				start = s;
				end = i;
			}

			if (max_ending_here < 0) {
				max_ending_here = 0;
				s = i + 1;
			}
		}
		// System.out.println("Maximum contiguous sum is " + max_so_far);
		// System.out.println("Starting index " + start);
		// System.out.println("Ending index " + end);

		int[] sum = new int[a.length];

		int ts = 0;
		for (int i = end; i >= start; i--) {
			sum[i] = ts;
			ts += a[i];

		}

		long ans = 0;

		for (int i = start; i <= end; i++) {

			ans += a[i] * sum[i];
		}

		System.out.println(ans);

	}

	static class Scan {
		private InputStream in;
		private byte[] buf = new byte[1024 * 1024];
		private int index;
		private int total;

		public Scan() {
			in = System.in;
			// try {
			// in = new FileInputStream(new File("/home/ujjwal/test/test"));
			// } catch (Exception ex) {
			//
			// }
		}

		public int scan() throws IOException {
			if (total < 0)
				throw new InputMismatchException();
			if (index >= total) {
				index = 0;
				total = in.read(buf);
				if (total <= 0)
					return -1;
			}
			return buf[index++];
		}

		public int scanInt() throws IOException {
			int integer = 0;
			int n = scan();
			while (isWhiteSpace(n))
				n = scan();
			int neg = 1;
			if (n == '-') {
				neg = -1;
				n = scan();
			}
			while (!isWhiteSpace(n)) {
				if (n >= '0' && n <= '9') {
					integer *= 10;
					integer += n - '0';
					n = scan();
				} else
					throw new InputMismatchException();
			}
			return neg * integer;
		}

		public long scanLong() throws IOException {
			long integer = 0;
			int n = scan();
			while (isWhiteSpace(n))
				n = scan();
			int neg = 1;
			if (n == '-') {
				neg = -1;
				n = scan();
			}
			while (!isWhiteSpace(n)) {
				if (n >= '0' && n <= '9') {
					integer *= 10;
					integer += n - '0';
					n = scan();
				} else
					throw new InputMismatchException();
			}
			return neg * integer;
		}

		public double scanDouble() throws IOException {
			double doub = 0;
			int n = scan();
			while (isWhiteSpace(n))
				n = scan();
			int neg = 1;
			if (n == '-') {
				neg = -1;
				n = scan();
			}
			while (!isWhiteSpace(n) && n != '.') {
				if (n >= '0' && n <= '9') {
					doub *= 10;
					doub += n - '0';
					n = scan();
				} else
					throw new InputMismatchException();
			}
			if (n == '.') {
				n = scan();
				double temp = 1;
				while (!isWhiteSpace(n)) {
					if (n >= '0' && n <= '9') {
						temp /= 10;
						doub += (n - '0') * temp;
						n = scan();
					} else
						throw new InputMismatchException();
				}
			}
			return doub * neg;
		}

		public String scanString() throws IOException {
			StringBuilder sb = new StringBuilder();
			int n = scan();
			while (isWhiteSpace(n))
				n = scan();
			while (!isWhiteSpace(n)) {
				sb.append((char) n);
				n = scan();
			}
			return sb.toString();
		}

		private boolean isWhiteSpace(int n) {
			if (n == ' ' || n == '\n' || n == '\r' || n == '\t' || n == -1)
				return true;
			return false;
		}
	}

	static class Print {
		private final BufferedWriter bw;

		public Print() {
			bw = new BufferedWriter(new OutputStreamWriter(System.out));
		}

		public void print(String str) throws IOException {
			bw.append(str);
		}

		public void printLine(String str) throws IOException {
			print(str);
			bw.append("\n");
		}

		public void close() throws IOException {
			bw.close();
		}
	}

}