#!/bin/python3

import sys

def solve(A):
    B = []
    for k in range(len(A)):
        for i in range(len(A)-k):
            j = i+k
            B.append(max(A[i:j+1]))
            
    return solve2(B)

def solve2(A):
    B = []
    for k in range(len(A)):
        for i in range(len(A)-k):
            j = i+k
            B.append(max(A[i:j+1]))
            
    
    return sum(B)    

if __name__ == "__main__":
    n = int(input().strip())
    A = list(map(int, input().strip().split(' ')))
    result = solve(A)
    print(result)