#!/bin/python

import sys

def solve(A):
    B =[]
    l = len(A)
    for k in xrange(l):
        for i in xrange(l-k):
            j=i+k
            B = B +[max(A[i:j+1])]
    l=l*(l+1)//2
    res = 0
    for k in xrange(l):
        for i in xrange(l-k):
            j=i+k
            res = (res +max(B[i:j+1]))
    return res%1000000000

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