/**
* Some things to do with slices
* @author ggtowell
* created: July 22, 2021
**/
package main

import "fmt"
/**
* Remove an element
* You need to actually return the slice because after compression
* The memory could get reallocated
* Note that this version keeps the order of the items in the
* original slice
* @param sl the slice
* @param loc the item to be removed
* @return the smaller slice
**/
func remove(sl []int, loc int) []int {
	if loc >= len(sl) || loc < 0 {
		return sl
	}
	copy(sl[loc:], sl[loc+1:])
	return sl[:len(sl)-1]
}

func removeValue(sl []int, val int) []int {
	loc:=0
	for ; loc<len(sl) && sl[loc]!=val; loc++ {} 
	return remove(sl, loc)	
}

/**
* reverse a slice
* Unlike remove, this sone does not need to return a slice object
* because this is guaranteed to be done in place
* @param sl the slice to be reversed
**/
func reverse(sl [] int) {
	ln := len(sl)
	fmt.Println(ln)
	for i:=0; i<ln/2; i++ {
		sl[i], sl[ln-i-1] = sl[ln-i-1], sl[i]
	}
}

/**
* Do some slicing
**/
func main() {
	var s []int // create a slice named s which is initially empty
	ll:=cap(s)  // cap is "capacity" how many ites the current slice can hold
	for i:=1;i<36;i++ {
		s = append(s, i)
		if ll != cap(s) {
			fmt.Printf("%d\n", cap(s))
			ll = cap(s)
		}
	}
	s=remove(s, 25) // remove the item at location 25.  Since slices are 0 indexed, this actually removes value 26
	s = removeValue(s, 25)
	s = removeValue(s, 60)
	fmt.Println(s[0:5])
	reverse(s)
	for ind,val := range s[3:7] {  // for loop over a piece of the slice
		fmt.Printf("%d %v\n", ind, val)
	}
	fmt.Println(s)
}