package main

import (
	"fmt"
	"reflect"
)

/**
 * A little go program showing the information stored about a slice
 * as information in inserted into 2 different slices. The interesting
 * thing about the preallocated slice is that it is more efficient. * * The one that starts empty has to move the data 4 times
 * to do 9 insertions -- the slice initially has space fo zero items,
 * then, on first add it creates a slice to store 1 item
 * (no data move), next add creates slice with 2 spaces (MOVE),
 * next add 4 spaces (MOVE), fifth add creates a slice with 8 spaces
 * (MOVE), ...
 *
 * @author gtowell
 * created: July 14, 2022
 * modified Oct 1 2022 gtowell added reflection to get the type
**/
func main() {
     aa := make([]int, 0, 11)
     var bb []int
     fmt.Printf("bb is a slice of type %v\n", reflect.TypeOf(bb))
     fmt.Printf("bb contains elements of type %v\n", reflect.TypeOf(bb).Elem())
     fmt.Printf("aa loc   %12p  %d   %d\n", aa, len(aa), cap(aa))
     fmt.Printf("bb loc   %12p  %d   %d\n", bb, len(bb), cap(bb))
     fmt.Printf("\n")
     for i:=1; i<10; i++ {
          aa = append(aa, i)
          bb = append(bb, i)
	     fmt.Printf("aa loc   %p  %d   %d\n", aa, len(aa), cap(aa))
     	fmt.Printf("bb loc   %p  %d   %d\n", bb, len(bb), cap(bb))
	     fmt.Printf("\n")
     }
}