[leetcode] 83. Remove Duplicates from Sorted List解題レポート


タイトル接続:https://leetcode.com/problems/remove-duplicates-from-sorted-list/
Given a sorted linked list, delete all duplicates such that each element appear only once.
For example, Given  1->1->2 , return  1->2 . Given  1->1->2->3->3 , return  1->2->3 .
構想:簡単な単鎖表削除のテーマ.何の罠もない.
コードは次のとおりです.
/**
 * 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 == NULL)    return NULL;
        int old = head->val;
        ListNode *p = head;
        while(p->next)
        {
            if(p->next->val == old)
            {
                ListNode* q = p->next;
                p->next = q->next;
                delete q;
            }
            else
            {
                old = p->next->val;
                p = p->next;
            }
        }
        return head;
    }
};