JZ-056-删除链表中重复的结点

删除链表中重复的结点

题目描述

在一个排序的链表中，存在重复的结点，请删除该链表中重复的结点，重复的结点不保留，返回链表头指针。例如，链表1->2->3->3->4->4->5 处理后为 1->2->5。

题目链接: 删除链表中重复的结点

代码

/**
 * 标题：删除链表中重复的结点
 * 题目描述
 * 在一个排序的链表中，存在重复的结点，请删除该链表中重复的结点，重复的结点不保留，返回链表头指针。 例如，链表1->2->3->3->4->4->5 处理后为 1->2->5
 * 题目链接：
 * https://www.nowcoder.com/practice/fc533c45b73a41b0b44ccba763f866ef?tpId=13&&tqId=11209&rp=1&ru=/ta/coding-interviews&qru=/ta/coding-interviews/question-ranking
 */
public class Jz56 {

    public ListNode deleteDuplication(ListNode pHead) {
        if (pHead == null || pHead.next == null) {
            return pHead;
        }
        ListNode next = pHead.next;
        if (pHead.val == next.val) {
            while (next != null && pHead.val == next.val) {
                next = next.next;
            }
            return deleteDuplication(next);
        } else {
            pHead.next = deleteDuplication(pHead.next);
            return pHead;
        }
    }

    public static void main(String[] args) {
        ListNode pHead = new ListNode(1);
        pHead.next = new ListNode(1);
        pHead.next.next = new ListNode(1);
        pHead.next.next.next = new ListNode(1);
        pHead.next.next.next.next = new ListNode(1);
        pHead.next.next.next.next.next = new ListNode(1);
        pHead.next.next.next.next.next.next = new ListNode(1);

        System.out.println("删除重复节点前的链表");
        ListNode cur = pHead;
        while (cur != null) {
            System.out.print(cur.val + " ");
            cur = cur.next;
        }
        System.out.println();

        System.out.println("删除重复节点后的链表");
        Jz56 jz56 = new Jz56();
        ListNode result = jz56.deleteDuplication(pHead);
        cur = result;
        while (cur != null) {
            System.out.print(cur.val + " ");
            cur = cur.next;
        }
    }
}