Reverse a singly linked list.
Hint:A linked list can be reversed either iteratively or recursively. Could you implement both?
反转一个单一的链表
算法分析
Java代码
/**
* Definition for singly-linked list.
* public class ListNode {
* int val;
* ListNode next;
* ListNode(int x) { val = x; }
* }
*/
public class Solution {
public ListNode reverseList(ListNode head) {
ListNode pre = null;
ListNode current = head;
while(current != null) {
ListNode nextTemp = current.next;
current.next = pre;
pre = current;
current = nextTemp;
}
return pre;
}
}
