Linked List Visualizer

Pointer Reversal

Trace prev, current, and next pointers as each node rewires its next reference to reverse the list in place.

AlgorithmO(n) time / O(1) space

Time

O(n)

Space

O(1)

Step Note

Start with prev as null and current at the head.

SampleDetails

function reverseList(head: ListNode | null) {
  let prev = null
  let current = head
  while (current !== null) {
    const next = current.next
    current.next = prev
    prev = current
    current = next
  }
  return prev
}