标签：.com cycle 距离 tno turn strong while memory begin
Intersection of Two Linked Lists
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.
Notes:
null.
可以将A,B两个链表看做两部分，交叉前与交叉后。例子中
交叉前A： a1 → a2
交叉前B: b1 → b2 → b3
交叉后AB一样： c1 → c2 → c3
所以 ，交叉后的长度是一样，所以，交叉前的长度差即为总长度差。
只要去除长度差，距离交叉点就等距了。
1 public ListNode getIntersectionNode(ListNode headA, ListNode headB) { 2 if(headA == null || headB == null) return null; 3 ListNode tempA = headA;// 计算链表长度用 4 ListNode tempB = headB; 5 int len_A = 1; 6 int len_B = 1; 7 while (tempA.next != null) {tempA = tempA.next; len_A++;}// 计算链表长度 8 while (tempB.next != null) {tempB = tempB.next; len_B++;} 9 int diff ;//长度差 10 //去除长度差 11 if(len_A > len_B){ 12 diff = len_A - len_B; 13 while(diff > 0){ 14 headA = headA.next; 15 diff--; 16 } 17 } 18 else if (len_A < len_B){ 19 diff = len_B - len_A; 20 while(diff > 0){ 21 headB = headB.next; 22 diff--; 23 } 24 } 25 while(headA != headB){ 26 headA = headA.next; 27 headB = headB.next; 28 } 29 return headA; 30 }
参考：
http://www.cnblogs.com/ganganloveu/p/4128905.html
[LeetCode]160.Intersection of Two Linked Lists
标签：.com cycle 距离 tno turn strong while memory begin
原文地址：http://www.cnblogs.com/zle1992/p/6804922.html
