给定一个排序链表,删除所有重复的元素,使得每个元素只出现一次。
示例 1:
输入: 1->1->2
输出: 1->2
示例 2:
输入: 1->1->2->3->3
输出: 1->2->3
一、思路
遇到重复的循环删除
C++代码:
class Solution {
public:
ListNode* deleteDuplicates(ListNode* head) {
ListNode *sentry = new ListNode(0);
sentry->next = head;
ListNode *cur = head, *pre = sentry;
while (cur != NULL) {
while (cur != NULL && cur->next != NULL && cur->val == cur->next->val)
cur->next = cur->next->next;
cur = cur->next;
}
return sentry->next;
}
};
执行效率: