Golang Slice interface and array concatenation

package main

import (
    "fmt"
)

func main() {
    // Slice Concatenation
    a := []int{1, 2, 3}
    b := []int{7, 12, 60}
    c := append(a, b...)
    fmt.Println(c)

    // Interface Slice Concatenation
    i := []interface{}{1, 2, 3}
    j := []interface{}{"Crosby", "Stills", "Nash", "Young"}
    k := append(i, j...)
    fmt.Println (k)

    // Array Concatenation
    l := [...]int{1, 2, 3}
    m := [...]int{7, 12, 60}
    var n [len (l) + len (m)] int
    copy(n[:], l[:])
    copy(n[len(l):], m[:])
    fmt.Println(n)
}

C:\golang\coding>go run example126.go
[1 2 3 7 12 60]
[1 2 3 Crosby Stills Nash Young]
[1 2 3 7 12 60]

C:\golang\coding>