lintcode-113-删除排序链表中的重复数字 II

113-删除排序链表中的重复数字 II

思路

code

/**
* Definition of ListNode
* class ListNode {
* public:
*     int val;
*     ListNode *next;
*     ListNode(int val) {
*         this->val = val;
*         this->next = NULL;
*     }
* }
*/
class Solution{
public:
/**
* @param head: The first node of linked list.
* @return: head node
*/
ListNode * deleteDuplicates(ListNode *head) {
// write your code here
if(head == NULL || head->next == NULL) {
return head;
}
ListNode *newHead = new ListNode(0);
ListNode *next = newHead;
ListNode *current = head;

while(current != NULL) {
if(current->next != NULL && current->val == current->next->val) {
while(current->next != NULL && current->val == current->next->val) {
current = current->next;
}
}
else {
next->next = current;
next = next->next;
}
current = current->next;
}
next->next = current;

return newHead->next;
}
};