import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.Scanner;

public class Solution {

    static int solve(int[] A) {
        Integer[] sa = maxTransform(new ArrayList<>(),  Arrays.stream( A ).boxed().toArray( Integer[]::new ));
        return Arrays.stream(maxTransform(new ArrayList<>(), sa)).mapToInt(i -> i).sum();
    }

    static Integer[] maxTransform(List<Integer> B, Integer[] A) {
        for (int k = 0; k <= A.length - 1; k++) {
            for (int i = 0; i <= A.length - k - 1; i++) {
                int j = i + k;
                int max = Arrays.stream(Arrays.copyOfRange(A, i, j+1)).mapToInt(i2 -> i2).max().getAsInt();
                B.add(max);
            }
        }
        return B.toArray(new Integer[B.size()]);
    }

    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();
    }
}