Leetcode160. 相交链表

题目传送:https://leetcode.cn/problems/intersection-of-two-linked-lists/submissions/

运行效率：

代码如下：

 public ListNode getIntersectionNode(ListNode headA, ListNode headB) {
        HashSet<ListNode> set = new HashSet<>();
        while (headA != null) {
            set.add(headA);
            headA = headA.next;
        }

        while (headB != null) {
            if (set.contains(headB)) {
                return headB;
            }
            headB = headB.next;
        }
        return null;
    }