[Linked List]Remove Duplicates from Sorted List

时间:2021-09-22 15:32:19
Total Accepted: 90247 Total Submissions: 254602 Difficulty: Easy

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.

/**
* 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* pre=NULL,*p=head,*next=NULL;
while(p){
if(pre && pre->val == p->val){
pre->next = p->next;
delete(p);
p = pre->next;
}else{
pre = p;
p = p->next;
}
}
return head;
}
};