import java.io.*;
import java.util.*;
import java.text.*;
import java.math.*;
import java.util.regex.*;

public class Solution {
    static int[] 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 j=0;
        int[] b=new int[end-start+1];
        for(int i=start;i<=end;i++)
        {
            b[j]=a[i];j++;
        }
        return b;
    }
    static long largestValue(int[] A) {
        // Return the largest value of any of A's nonempty subarrays.
        int n=A.length;
        //int[] c=new int[n];
        int[] c=maxSubArraySum(A, n);
        long l=0;
        for(int i=0;i<c.length;i++)
        {System.out.println(c[i]);
           for(int j=i+1;j<c.length;j++)
           {
               //System.out.println(c[i]+" ,"+c[j]);
               l+=(c[i]*c[j]);
           }
        }  //System.out.println(c[i]);
            
        return l;
    }

    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        int n = in.nextInt();
        int[] A = new int[n];
        for(int A_i = 0; A_i < n; A_i++){
            A[A_i] = in.nextInt();
        }
        long result = largestValue(A);
        System.out.println(result);
        in.close();
    }
}