go 函数传参切片不确定个数

package main

import "fmt"

func calc(a , b int) (int,int){	
	sum := a+b
	sub := a-b
	return sum,sub
}

func calc1(a , b int) (sum int,sub int){	
	sum = a+b
	sub = a-b
	return
}

func calc_v1(b ...int) int{	
	sum := 0
	for i:=0;i