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

public class Solution {

    static int solve(int[] A) {
        //  Return the length of the longest possible sequence of moves modulo 10^9+7.
        List list = s(A);
        int[] B = new int[list.size()];
        for(int i =0;i<list.size();i++){
            B[i]=(int)list.get(i);
        }
        List list1 = s(B);
        int sum =0;
        for(int i =0;i<list1.size();i++){
            sum+=(int)list1.get(i);
        }
        return sum;
    }
    
    static List s(int[] a){
        List list = new ArrayList();
        for(int k=0; k<a.length; k++){
            for(int i=0; i<a.length-k; i++){
                int j = i+k;
                list.add(maxValue(a,i,j));
            }
        }
        return list;
    }
    
    static int maxValue(int[] A,int x, int j){
        List l = new ArrayList();
        for(int i=x; i<=j;i++){
            l.add(A[i]);
        }
        Collections.sort(l,Collections.reverseOrder());
        return (int)l.get(0);
    }

    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();
        }
        int result = solve(a);
        System.out.println(result);
        in.close();
    }
}