题目:
Given a sorted linked list, delete all nodes that have duplicate numbers, leaving only distinct numbers from the original list.
For example,
Given 1->2->3->3->4->4->5
, return 1->2->5
.
Given 1->1->1->2->3
, return 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 || head->next == NULL)
return head;
ListNode *cur = head;
while(cur->next != NULL && cur->val == cur->next->val)
cur = cur->next;
if(head != cur) {
while(head != cur->next) {
ListNode *tmp = head;
head = head->next;
delete tmp;
}
return deleteDuplicates(head);
}
head->next = deleteDuplicates(head->next);
return head;
}
};