public/subjects/listclear.md

# listpushback

## Instructions

Write a function `ListClear` that delets all `nodes` from a linked list, deleting the link between the list.

- Tip: assign the list's pointer to nil 

## Expected function and structure

```go
type Node struct {
	Data interface{}
	Next *Node
}

type List struct {
	Head *Node
	Tail *Node
}

func ListClear(l *List) {

}
```

## Usage

Here is a possible [program](TODO-LINK) to test your function :

```go
package main

import (
	"fmt"
	piscine ".."
)

type List = piscine.List
type Node = piscine.Node

func PrintList(l *List) {
	link := l.Head
	for link != nil {
		fmt.Print(link.Data, " -> ")
		link = link.Next
	}
	fmt.Println(nil)
}

func main() {
	link := &List{}

	piscine.ListPushBack(link, "I")
	piscine.ListPushBack(link, 1)
	piscine.ListPushBack(link, "something")
	piscine.ListPushBack(link, 2)

	fmt.Println("------list------")
	PrintList(link)
	piscine.ListClear(link)
	fmt.Println("------updated list------")
	PrintList(link)
}

```

And its output :

```console
student@ubuntu:~/piscine/test$ go build
student@ubuntu:~/piscine/test$ ./test
------list------
I -> 1 -> something -> 2 -> <nil>
------updated list------
<nil>
student@ubuntu:~/piscine/test$
```