Description：

Write a program to find the node at which the intersection of two singly linked lists begins.

For example, the following two linked lists:

A:          a1 → a2                   ↘                     c1 → c2 → c3                   ↗            B:     b1 → b2 → b3

begin to intersect at node c1.

求两个链表的相交的部分

/** * 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 aNode = headA;        ListNode bNode = headB;        int aLen = 0, bLen = 0;        while(aNode != null) {            aLen ++;            aNode = aNode.next;        }        while(bNode != null) {            bLen ++;            bNode = bNode.next;        }        if(aNode != bNode)             return null;        if(aLen > bLen) {             for(int i = 0; i < aLen-bLen; i++)                headA = headA.next;        }        else if(aLen < bLen) {            for(int i=0; i