把两个链表互相连接起来就好。
1->2->3
2->3
1->2->3->2->3
2->3->1->2->3
public ListNode getIntersectionNode(ListNode headA, ListNode headB) {
ListNode a = headA;
ListNode b = headB;
while (a != b) {
if (a == null) {
a = headB;
} else {
a = a.next;
}
if (b == null) {
b = headA;
} else {
b = b.next;
}
}
return a;
}
