1+ /*
2+ Author: King, wangjingui@outlook.com
3+ Date: Dec 12, 2014
4+ Problem: Remove Nth Node From End of List
5+ Difficulty: Medium
6+ Source: https://oj.leetcode.com/problems/remove-nth-node-from-end-of-list/
7+ Notes:
8+ Given a linked list, remove the nth node from the end of list and return its head.
9+ For example,
10+ Given linked list: 1->2->3->4->5, and n = 2.
11+ After removing the second node from the end, the linked list becomes 1->2->3->5.
12+ Note:
13+ Given n will always be valid.
14+ Try to do this in one pass.
15+
16+ Solution: head---back------front------>NULL
17+ | |
18+ ---> n <----
19+ */
20+
21+ /**
22+ * Definition for singly-linked list.
23+ * public class ListNode {
24+ * int val;
25+ * ListNode next;
26+ * ListNode(int x) {
27+ * val = x;
28+ * next = null;
29+ * }
30+ * }
31+ */
32+ public class Solution {
33+ public ListNode removeNthFromEnd (ListNode head ,int n ) {
34+ ListNode dummy =new ListNode (0 );
35+ ListNode back =dummy ,front =dummy ;
36+ dummy .next =head ;
37+ while (n -- !=0 )front =front .next ;
38+ while (front .next !=null ) {
39+ front =front .next ;
40+ back =back .next ;
41+ }
42+ back .next =back .next .next ;
43+ return dummy .next ;
44+ }
45+ }
