题目:
Given a sorted linked list, delete all duplicates such that each element appear only once.
Example 1:
Input: 1->1->2 Output: 1->2
Example 2:
Input: 1->1->2->3->3 Output: 1->2->3
代码:
/**
* 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)return NULL;
ListNode* p = head->next;
ListNode* first = new ListNode(0);
first->next = head;
while (p) {
while (p&&head->val == p->val) {
p = p->next;
}
head->next = p;
head = p;
}
return first->next;
}
};