Question

题目内容

解题思路

哈希。

代码实现

/**
 * Definition for singly-linked list.
 * class ListNode {
 *     val: number
 *     next: ListNode | null
 *     constructor(val?: number, next?: ListNode | null) {
 *         this.val = (val===undefined ? 0 : val)
 *         this.next = (next===undefined ? null : next)
 *     }
 * }
 */

const getIntersectionNode = (
  headA: ListNode | null,
  headB: ListNode | null
): ListNode | null => {
  let setA = new Set<ListNode>();
  let curr = headA;
  while (curr !== null) {
    setA.add(curr);
    curr = curr.next;
  }
  curr = headB;
  while (curr !== null) {
    if (setA.has(curr)) return curr;
    curr = curr.next;
  }
  return null;
};