Partition List
Link: http://oj.leetcode.com/problems/partition-list/
Given a linked list and a value x, partition it such that all nodes less than x come before nodes greater than or equal to x.
You should preserve the original relative order of the nodes in each of the two partitions.
For example,
Given 1->4->3->2->5->2
and x = 3,
return 1->2->2->4->3->5
.
1 /** 2 * Definition for singly-linked list. 3 * public class ListNode { 4 * int val; 5 * ListNode next; 6 * ListNode(int x) { 7 * val = x; 8 * next = null; 9 * } 10 * } 11 */ 12 public class Solution { 13 public ListNode partition(ListNode head, int x) { 14 ListNode remains = new ListNode(0); 15 ListNode remains_point = remains; 16 ListNode result = new ListNode(0); 17 ListNode result_point = result; 18 while(head!=null){ 19 if(head.val<x) { 20 result.next = head; 21 result = result.next; 22 head = head.next; 23 }else { 24 remains.next=head; 25 remains = remains.next; 26 head = head.next; 27 } 28 } 29 if(remains_point.next!=null){ 30 result.next=remains_point.next; 31 //Note we should end the remains link list 32 remains.next=null; 33 } 34 return result_point.next; 35 } 36 }
第一题提交没通过。因为remains链表没有加终止。