Java实现单链表反转_java单向链表的反转

使用Java将链表从 a->b->c 的状态转移为 c->b>a 并且返回新链表的头结点

代码实现：

public static class ListNode {
        int val;
        ListNode next;
 
        ListNode() {
        }
 
        ListNode(int val) {
            this.val = val;
        }
 
        ListNode(int val, ListNode next) {
            this.val = val;
            this.next = next;
        }
    }

public ListNode reverseV(ListNode head){
        if(head == null || head.next == null)
            return head;
 
        //声明尾结点并指向空 头结点刷新
         ListNode tail = head;
         head = head.next;
         tail.next = null;
         
         while(head != null){
             ListNode tmp = head.next;
             head.next = tail;
             tail = head;
             head = tmp;
         }
 
        return tail;
    }