leetcode 刷题之路 76 Remove Duplicates from Sorted List

Given a sorted linked list, delete all duplicates such that each element appear only once.

For example,

Given 1->1->2,
return 1->2.

Given 1->1->2->3->3, return 1->2->3.

删除排序链表中重复的节点,删除操作完成后,原链表中的重复节点只保留一个。

思路,遍历链表,如果当前节点和下一个节点重复,则删除下一个节点,不同则前进一个节点继续处理,直到链表结尾。

这道题比Remove Duplicateds from Sorted list II要简单一些,在删除完重复的下一个节点后,不需要再删除当前节点。

AC code:

/**
 * Definition for singly-linked list.
 * struct ListNode {
 *     int val;
 *     ListNode *next;
 *     ListNode(int x) : val(x), next(NULL) {}
 * };
 */
class Solution {
public:
    ListNode *deleteDuplicates(ListNode *head)
    {
        ListNode *p=head;
        while(p!=NULL)
        {
            if(p->next==NULL||p->val!=p->next->val)
            {
                p=p->next;
                continue;
            }
            ListNode *q=p->next;
            p->next=q->next;
            delete q;
        }
        return head;
    }
};

leetcode 刷题之路 76 Remove Duplicates from Sorted List

时间: 2024-11-06 03:27:00

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