mod=1000000007
n=int(input())
a=list(map(int,input().split()))
b1=[]
ans=0
for k in range(n):
    for i in range(n-k):
        j=i+k
        maximum=-999999999999
        for t in range(i,j+1):
            maximum=max(maximum,a[t])
        b1.append(maximum)
#print(b1)
#ans+=sum(b1)
n=len(b1)
b2=[]
for k in range(n):
    for i in range(n-k):
        j=i+k
        maximum=-999999999999
        for t in range(i,j+1):
            maximum=max(maximum,b1[t])
        b2.append(maximum)
        ans+=maximum
print(ans)