#!/bin/python3

import sys

def solve(A):
    l1 = []
    l = len(A)
    for k in range(l):
        for i in range(l-k):
            j = i+k
            m = max(A[i:j+1])
            l1.append(m)
    
    return l1    

if __name__ == "__main__":
    s = 0
    n = int(input().strip())
    A = list(map(int, input().strip().split(' ')))
    result = solve(A)
    ans = solve(result)
    for i in ans:
        s = s+ i
    print(s)