remove-duplicates-from-sorted-list.cpp

/**
 * 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) {
        
        ListNode* pre = head;
        ListNode* cur = NULL;
        if(pre != NULL)
            cur = pre->next;
        while(cur != NULL){
            if(pre->val == cur->val){
                cur = cur->next;
                pre->next = cur;
            }
            else{
                pre = cur;
                cur=cur->next;
            }
        }
        return head;
    }
};