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

public class Solution {

    static int solve(Integer[] A) {
        //  Return the sum of S(S(A)) modulo 10^9+7.
        //  ArrayList<Integer> B = new ArrayList<Integer>();
        //  ArrayList<Integer> C = new ArrayList<Integer>();
        ArrayList<Integer> B = new ArrayList<Integer>();
        
        for(int k = 0; k < A.length; k++){
            for(int i = 0; i < A.length - k; i++){
                int j = i+ k;
                Integer[] A1 = Arrays.copyOfRange(A, i, j + 1);
                 //for(Integer d : A1)
            //System.out.print(d + " ");
                B.add(Collections.max(Arrays.asList(A1)));
            }
        }
        //for(Integer d : B)
            //System.out.print(d + " ");
        //System.out.println();
         ArrayList<Integer> C = new ArrayList<Integer>();
        for(int k = 0; k < B.size(); k++){
            for(int i = 0; i < B.size() - k; i++){
                int j = i+ k;
                
                List<Integer> B1 = B.subList(i, j+1);
               
                C.add(Collections.max(B1));
            }
        }
        //for(Integer d : C)
           // System.out.print(d + " ");
        
        int sum = 0;
        for(Integer d : C)
          sum += d;
          
        return sum;

    }

    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        int n = in.nextInt();
        Integer[] A = new Integer[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();
    }
}