/** * Definition for singly-linked list. * public class ListNode { * int val; * ListNode next; * ListNode(int x) { * val = x; * next = null; * } * } */ public class Solution { public ListNode getIntersectionNode(ListNode headA, ListNode headB) { if(headA == null || headB == null) return null; ListNode a = headA; ListNode b = headB; while (a != b) { a = a == null? headB : a.next; b = b == null? headA : b.next; } return a; } }

Explain this code and can you explain what does the code inside while loop do?