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

public class Solution {

    static int solve(int[] A)
    {
    int l= A.length;
        
        int i,j,k,count=0;
        
        int sum=0;
        StringBuilder str=new StringBuilder("");
        int temps=0;
        int max= -10;
        
        int B[] =new int[1000000];
       
        
        for(k=0;k<=l-1;k++)
        {
         max=-10;
            for(i=0 ;i<= l-k-1 ;i++)
            {                             // 3 2 1
                j=i+k;
                max=-10;
                for(int tp=i;tp<=j;tp++ )
                {
                max=Math.max(max,A[tp]);   // 3 2 1    k=1   3 2 
                } 
                 //   System.out.println(max+" ddk "  + k+ " ddi " + i+ " cdc " + j);
                B[count]=max;
                count++;
                    // 3 2 1 
                
            }
            
        }
        l=count;
        
        for(k=0;k<=l-1;k++)
        {
         max=-10;
            for(i=0 ;i<= l-k-1 ;i++)
            {                             // 3 2 1
                j=i+k;
                max=-10;
                for(int tp=i;tp<=j;tp++ )
                {
                max=Math.max(max,B[tp]);   // 3 2 1    k=1   3 2 
                } 
            
                sum=sum+max;
                //        System.out.println(max+" ddk "  + k+ " ddi " + i+ " cdc " + j);
                
                    // 3 2 1 
                
            }
            
        }
        
        
        
       
        return sum ;
    
    }

    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();
    }
}