关于java:JZ015反转链表

反转链表

题目形容

输出一个链表，反转链表后，输入新链表的表头。

题目链接: 反转链表

代码

/** * 题目：反转链表 * 题目形容 * 输出一个链表，反转链表后，输入新链表的表头。 * 题目链接： * https://www.nowcoder.com/practice/75e878df47f24fdc9dc3e400ec6058ca?tpId=13&&tqId=11168&rp=1&ru=/ta/coding-interviews&qru=/ta/coding-interviews/question-ranking */public class Jz15 {    public ListNode reverseList(ListNode head) {        if (head == null || head.next == null) {            return head;        }        ListNode first = head, second = head.next;        first.next = null;        while (first != null && second != null) {            ListNode temp = first;            first = second;            second = second.next;            first.next = temp;        }        return first;    }    public static void main(String[] args) {        ListNode head = new ListNode(1);        head.next = new ListNode(2);        head.next.next = new ListNode(3);        System.out.println("before reverse");        ListNode cur = head;        while (cur != null) {            System.out.print(cur.val + " ");            cur = cur.next;        }        System.out.println();        Jz15 jz15 = new Jz15();        ListNode result = jz15.reverseList(head);        System.out.println("after reverse");        ListNode cur1 = result;        while (cur1 != null) {            System.out.print(cur1.val + " ");            cur1 = cur1.next;        }    }}

【每日寄语】 生存的实质就是幸福的活着，而生存的智慧就是活出本人想要的样子。