#!/bin/python3

import sys

def solve(A):
    #  Return the length of the longest possible sequence of moves modulo 10^9+7.
    err = 0
    B = []
    C = []
    D = []
    finalResult = 0
    for x in range (len(A)):
        if A[x] < 1 and A[x] > 10**6:
            err = 1
    if err != 1:
        for k in range (len(A)):
            for i in range (len(A) - k):
                j= i + k
                D = A[i:j+1]
                D.sort(reverse=True)
                B.append(D[0])
        D = []
        for k in range (len(B)):
            for i in range (len(B) - k):
                j= i + k
                D = B[i:j+1]
                D.sort(reverse=True)
                C.append(D[0])

        for x in range (len(C)):
            finalResult += int(C[x])
        return finalResult

if __name__ == "__main__":
    n = int(input().strip())
    if n >=1 and n <= 2 * (10**5):
        a = list(map(int, input().strip().split(' ')))
        result = solve(a)
        print(result)