package main
 
import (
  "fmt"
  "sort"
)
 
func main() {
 
  var n int
  fmt.Scan(&n)
  value := make([]int, n)
  
  for i := 0; i < n; i++ {
    fmt.Scan(&value[i])
  }

  sort.Sort(sort.IntSlice(value))
  max := value[0]
  
  for i := 1; i <= n-1; i++ {
    max = (max + value[i]) / 2
  }
  
  fmt.Println(max)
}  