题目：

Reverse a singly linked list.

 

思路1：直接用循环遍历即可

 

代码：

public static ListNode reverseList(ListNode head) {        if(head == null || head.next == null){            return head;        }                ListNode nodeCurrent = head.next;        ListNode nodeLast= head;                head.next = null;                while(nodeCurrent != null){            ListNode tempNode = nodeCurrent.next;            nodeCurrent.next = nodeLast;            nodeLast = nodeCurrent;            nodeCurrent = tempNode;        }                return nodeLast;    }

 

思路2：递归

public static ListNode reverseList(ListNode head) {        if(head == null || head.next == null){            return head;        }                ListNode nodeCurrent = head.next;          ListNode nodeNext = reverseList(nodeCurrent);                  head.next = null;          nodeCurrent.next = head;                  return nodeNext;    }