LeetCode Reverse Linked List II

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Reverse a linked list from position m to n. Do it in-place and in one-pass.

For example:
Given 1->2->3->4->5->NULL, m = 2 and n = 4,

return 1->4->3->2->5->NULL.

Note:
Given m, n satisfy the following condition:
1 ≤ m ≤ n ≤ length of list.

思路：把这一段截取出来回文的形式交换。

/**
 * Definition for singly-linked list.
 * public class ListNode {
 *     int val;
 *     ListNode next;
 *     ListNode(int x) {
 *         val = x;
 *         next = null;
 *     }
 * }
 */
public class Solution {
    public ListNode reverseBetween(ListNode head, int m, int n) {
         List<ListNode> list  = new ArrayList<ListNode >();
		 
		 ListNode cur = head;
		 for (int i = 1; i < m; i++)
			 cur = cur.next;
		 
		 for (int i = m; i <= n; i++) {
			 list.add(cur);
			 cur = cur.next;
		 }
		
		 int size = list.size();
		 for (int i = 0; i < size/2; i++) {
			int tmp = list.get(i).val;
			list.get(i).val = list.get(size-1-i).val;
			list.get(size-1-i).val = tmp;
		 }
		 
		 return head;
    }
}

LeetCode Reverse Linked List II

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原文地址：http://blog.csdn.net/u011345136/article/details/45075231