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.
answer:
/**
* Definition for singly-linked list.
* struct ListNode {
* int val;
* ListNode *next;
* ListNode(int x) : val(x), next(NULL) {}
* };
*/
class Solution {
public:
void help( ListNode* &head)
{
if(!head||!head->next)return ;
if(head->val!=head->next->val)help(head->next);
else{
while(head->next&&head->val==head->next->val)
{
head=head->next;
}
head=head->next;
help(head);
}
}
ListNode* deleteDuplicates(ListNode* head) {
help(head);
return head;
}
};
leetcode: Remove Duplicates from Sorted List II
原文：http://www.cnblogs.com/steel-wang/p/4651224.html