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

n=int(input())
a=list(map(int,input().split()))

a+=s(a)

a+=s(a)
print(sum(a))