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Discussion on: Leetcode - Reverse Linked List(with JavaScript)

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Replies for: Could you elaborate with an example? I have been struggling with these concepts for a couple of days now. I went about trying to turn a linked list...

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pentacular profile image
pentacular •

Using a stack abstraction

const push = (item, list) => ({ item, next: list });
const pop = (list) => [list.next, list.item];
const reverse = (list) => {
  let reversed = null;
  while (list !== null) {
    [list, item] = pop(list);
    reversed = push(reversed, item);
  }
  return reversed;
}
console.log(JSON.stringify(reverse(push(3, push(2, push(1, null))))));
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Or, if you prefer recursion

const push = (item, list) => ({ item, next: list });
const reverse = (list, reversed = null) =>
  list === null
    ? reversed
    : reverse(list.next, push(list.item, reversed));
console.log(JSON.stringify(reverse(push(3, push(2, push(1, null))))));
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codefinity profile image
Manav Misra •

I prefer recursion. Tx.