Total Accepted: 59433 Total Submissions: 230628 Difficulty: Medium
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.
class Solution {
public:
ListNode* deleteDuplicates(ListNode* head) {
ListNode* help_node = new ListNode();
help_node->next = head;
ListNode* cur_pre = help_node;
ListNode* cur = head;
while(cur!=NULL){
ListNode* p = cur->next;
while(p!=NULL && p->val==cur->val){
p = p->next;
}
if(p != cur->next){
while(cur != p) {
ListNode* tmp = cur;
cur = cur->next;
delete (tmp);
}
cur_pre->next = p;
cur = p;
}else{
cur_pre = cur;
cur = cur->next;
}
}
head = help_node->next;
delete (help_node);
return head;
}
};