GO求平均值

package main
 
import "fmt"
 
func main(){
    sum:=0.0
    avg:=0.0
    xs:=""
    switch len(xs){
        case :
        avg=
        default:
        for _,v:=range xs{
            sum+=float64(v)
        }
        avg=sum/float64(len(xs))
    }
 
    fmt.Println(float64(len(xs)))
 
    fmt.Println(sum)
 
    _=avg;
    fmt.Println(avg)
 
}