逆转单链表c#模拟实现

来源：互联网发布：论李维知乎编辑：程序博客网时间：2024/05/17 22:52

/// <summary>
     /// 模拟单链表
     /// </summary>
    class LinkNode
    {
        public object data;
        public LinkNode next;

        public LinkNode(object adata)
        {
            this.data = adata;
        }
    }

    class LinkUtil
    {
         /// <summary>
         /// 反转单链表,用两个辅助节点
         /// </summary>
         /// <param name="node"></param>
         /// <returns></returns>
        public static LinkNode Inverse(LinkNode node)
        {

            // r,q,p 一步一步，像走路一样
            // p总是指向下一个节点
            //q 用来跟上p
            //r 用来存储断开的节点
            LinkNode r = null;
            LinkNode q = null;
            LinkNode p = node;

            while (p != null)
            {
                r = q;
                q = p;
                p = p.next;
                q.next = r;
            }

return q;

        }
        /// <summary>
        /// 打印单链表
        /// </summary>
        /// <param name="list"></param>
        public static void PrintList(LinkNode list)
        {
            LinkNode p=list;
            while (p != null)
            {
                Console.WriteLine(p.data);
                p = p.next;
            }
        }

        /// <summary>
        /// 测试
        /// </summary>
        /// <param name="args"></param>
        static void Main(string[] args)
        {
            LinkNode n1 = new LinkNode("1");
            LinkNode n2 = new LinkNode("2");
            LinkNode n3 = new LinkNode("3");
            LinkNode n4 = new LinkNode("4");

            n1.next = n2;
            n2.next = n3;
            n3.next = n4;
            Console.WriteLine("before reverse:");
            PrintList(n1);
            Console.WriteLine("after reverse:");
            LinkNode head= Inverse(n1);

            PrintList(head);

Console.Read();

}
}