相交链表

 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  */
14 var getIntersectionNode = function(headA, headB) {
15     let n1 = headA
16     let n2 = headB
17     while(n1!=n2){
18         if(n1 === null ){
19             n1 = headB
20         }else{
21             n1 = n1.next
22         }
23         if(n2 === null ){
24             n2 = headA
25         }else{
26             n2 = n2.next
27         }
28     }
29     return n1
30 };