#!/bin/python

import sys

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

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