package main
import "fmt"
import "sort"

func main() {
 //Enter your code here. Read input from STDIN. Print output to STDOUT
    var n,sum int
    fmt.Scan(&n)
    arr := make([]int,n)
    for i := range arr {
        fmt.Scan(&arr[i])
    }
    b := []int{}
    for k := range arr {
        for i := 0; i < n-k; i++ {
            j := i+k
            p := make([]int,j-i+1)
            copy(p,arr[i:j+1])
            sort.Ints(p)
            b = append(b,p[len(p)-1])
        }
    }
    arr = []int{}
    n = len(b)
    for k := range b {
        for i := 0; i < n-k; i++ {
            j := i+k
            p := make([]int,j-i+1)
            copy(p,b[i:j+1])
            sort.Ints(p)
            arr = append(arr,p[len(p)-1])
            sum += arr[len(arr)-1]
        }
    }
    fmt.Println(sum)
}