LC 160. Intersection of Two Linked Lists

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/**
 * Definition for singly-linked list.
 * function ListNode(val) {
 *     this.val = val;
 *     this.next = null;
 * }
 */

/**
 * @param {ListNode} headA
 * @param {ListNode} headB
 * @return {ListNode}
 */
var getIntersectionNode = function(headA, headB) {
  const visited = new Set()
  let temp = headA
  while (temp !== null) {
    visited.add(temp)
    temp = temp.next
  }
  temp = headB
  while (temp !== null) {
    if (visited.has(temp)) {
      return temp
    }
    temp = temp.next
  }
  return null
};