In a Singly Linked List, each node has only a pointer to the next node, and there are some ways to reverse it, the one that I want to show here doesn't require extra space.

In this algorithm, we start from the list's head, and we use three pointers, each one for **previous node**, **current node** and **next node**.
In the beginning, The **current** and the **next** points to the list's head, and the **previous** points to null. While the **current** are pointing to a node we do the following:

**next**point to its next node**current.next**points to**previous node****previous node**points to the**current node****current node**points to**next node**

This loop continues until the current points to null, which will mean that we reached the end of the list. Like this:

`1prev = null; 2current = head; 3next = head; 4 5while (current !== null) { 6 next = next.next; 7 current.next = prev; 8 prev = current; 9 current = next; 10}`

A single iteration works like this:

This algorithm may vary according to the Linked List implementation, using this implementation, looks like this:

```
1function reverse(linkedList: LinkedList<number>) {
2 let prev = null;
3 let current = linkedList.head;
4 let next = linkedList.head;
5
6 while (current !== null) {
7 next = next.next;
8 current.next = prev;
9 prev = current;
10 current = next;
11 }
12
13 linkedList.head = prev;
14}
15
16const linkedList = new LinkedList((a: number, b: number) => a === b);
17
18linkedList.append(1);
19linkedList.append(2);
20linkedList.append(3);
21linkedList.append(4);
22linkedList.append(5);
23
24reverse(linkedList);
25
26linkedList.traverse();
```