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) { if(head==NULL) return head; ListNode *p=head,*q; while(p) { q=p->next; while(q&&p->val==q->val) q=q->next; p->next=q; p=p->next; } return head; } };