package main

import (
    "fmt"
    "math/rand"
    "time"
)

func main() {
    rand.Seed(time.Now().UnixNano())
    a := []int{1, 2, 3, 4, 5}
    for i := len(a) - 1; i > 0; i-- {
        j := rand.Intn(i + 1)
        a[i], a[j] = a[j], a[i]
    }
    fmt.Println(a)

    // You can also use rand.Shuffle
    b := []int{6, 7, 8, 9, 10}
    rand.Shuffle(len(b), func(i, j int) {
        b[i], b[j] = b[j], b[i]
    })
    fmt.Println(b)
}