#!/bin/python3

import sys

def solve(A):
    B = []
    #  Return the sum of S(S(A)) modulo 10^9+7.
    for k in range(0,len(A)):
        for i in range(0,len(A)-k):
            j = i + k
            B.append(max(A[i:j+1]))
    return B

if __name__ == "__main__":
    n = int(input().strip())
    a = list(map(int, input().strip().split(' ')))
    result = solve(solve(a))
    result = sum(result[0:len(result)])
    print(result)