LeetCode: Intersection Of Two Linked Lists Solution

1/**
2 * Definition for singly-linked list.
3 * function ListNode(val) {
4 *     this.val = val;
5 *     this.next = null;
6 * }
7 */
8
9/**
10 * @param {ListNode} headA
11 * @param {ListNode} headB
12 * @return {ListNode}
13 */
14var getIntersectionNode = function (headA, headB) {
15  let res = null
16  let set = new WeakSet()
17  while (headA) {
18    set.add(headA)
19    headA = headA.next
20  }
21  while (headB) {
22    if (set.has(headB)) {
23      res = headB
24      break
25    }
26    headB = headB.next
27  }
28  return res
29}