package main

import (
    "fmt"
)

func main() {
    a := []int{1, 2, 3, 4, 5}
    for i := len(a)/2 - 1; i >= 0; i-- {
        opp := len(a) - 1 - i
        a[i], a[opp] = a[opp], a[i]
    }
    fmt.Println(a)
}