Go-切片

切片的长度、容量

package main

import "fmt"

func main() {
    a := []int{0, 1, 2, 3, 4, 5, 6, 7, 8, 9}
    s1 := a[:]
    fmt.Println("s1=", s1)
    fmt.Printf("len=%d, cap=%d\n", len(s1), cap(s1))

    s2 := a[3:6:7]
    fmt.Println("s2=", s2)
    fmt.Printf("len=%d, cap=%d\n", len(s2), cap(s2))

    s3 := a[:6]
    fmt.Println("s3=", s3)
    fmt.Printf("len=%d, cap=%d\n", len(s3), cap(s3))

    s4 := a[3:]
    fmt.Println("s4=", s4)
    fmt.Printf("len=%d, cap=%d\n", len(s4), cap(s4))
}

切片的copy

package main

import "fmt"

func main() {
    srcSlice := []int{1, 2, 3, 4}
    dstSlice := []int{1, 1, 1, 1}

    copy(dstSlice, srcSlice)
    fmt.Println("dst = ", dstSlice)
}

切片的append特点

package main

import "fmt"

func main() {
    s := make([]int, 0, 1)
    oldCap := cap(s)
    fmt.Println("s= ", s)
    fmt.Println("oldCap= ", oldCap)

    s = append(s, 1)
    fmt.Println("s= ", s)
    fmt.Println("1 newCap= ", cap(s))

    s = append(s, 2)
    fmt.Println("s= ", s)
    fmt.Println("2 newCap= ", cap(s))

    s = append(s, 3)
    fmt.Println("s= ", s)
    fmt.Println("3 newCap= ", cap(s))

    // s = append(s, 4)
    // fmt.Println("s= ", s)
    // fmt.Println("4 newCap= ", cap(s))
}