#!/bin/python3

import sys

def solve(A):
    b=[]
    s=0
    for k in range(0,len(A)):
        for i in range(0,len(A)-k):
            m=[]
            j=i+k
            for l in range(i,j+1):
                m.append(A[l])
            b.append(max(m))
    c=[]
    for k in range(0,len(b)):
        for i in range(0,len(b)-k):
            m=[]
            j=i+k
            for l in range(i,j+1):
                m.append(b[l])
            c.append(max(m))
    for i in c:
        s=s+i
    return(s)

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