Slices / Create a slice / Essential Go

package main

import (
	"fmt"
)

func main() {
	n := 30
	a := make([]int, 0, n)
	fmt.Printf("a has lenght %d and capacity %d\n", len(a), cap(a))
	for i := 0; i < n; i++ {
		a = append(a, i)
	}
	fmt.Printf("a has lenght %d and capacity %d\n", len(a), cap(a))
}