Remove Duplicates from Sorted List

/**
 * 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)
        {
            ListNode *p,*q;
            p=head;
            if(p->next)
            {
                q=p->next;
            }
            while(p->next)
            {
                if(p->val==q->val)
                {
                    p->next=q->next;
                    free(q);
                    q=p->next;
                }
                else
                {
                    p=q;
                    q=p->next;
                }
            }
        }
        return head;
    }
};

代码写的好看一些

/**
 * 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)
        {
            ListNode *p,*q;
            p=head;
            while(p->next)
            {
                q=p->next;
                if(p->val==q->val)
                {
                    p->next=q->next;
                    free(q);
                }
                else
                {
                    p=q;
                }
            }
        }
        return head;
    }
};