11.切片的使用

package main
import "fmt"
func main() {
    //长度为3，容量为5
    var numbers = make([]int,3,5)
    fmt.Println(len(numbers),cap(numbers),numbers)
    //追加元素
    numbers=append(numbers,1)
    numbers=append(numbers,2)
    fmt.Println(len(numbers),cap(numbers),numbers)
    numbers=append(numbers,3)
    //扩容为容量的2倍
    fmt.Println(len(numbers),cap(numbers),numbers)
    var number2=make([]int,3)
    fmt.Println(len(number2),cap(number2),number2)
    number2=append(number2,1)
    //扩容长度的2倍
    fmt.Println(len(number2),cap(number2),number2)
}

package main
import "fmt"
func main() {
    s :=[]int{1,2,3}
    //[0:2)
    s1 :=s[0:2]  //索引0和1的值
    fmt.Println(s1)
    s2:=make([]int,3)
    //数组拷贝
    copy(s2,s)
    fmt.Println(s2)
}