题目大意:给定一个链表,要求将相邻重复的节点给删除
解题思路:最开始找到一个pre节点,这个pre节点表示从开始到pre这个节点,链表已经去重
那么这个节点表示上一次不重复的节点
/**
* 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 || head->next == NULL) {
return head;
}
ListNode *pre = NULL, *newHead = NULL;
ListNode *cur = head;
bool find = false;
while(cur != NULL) {
ListNode *tmp = cur;
find = false;
cur = cur->next;
while(cur != NULL && tmp->val == cur->val) {
cur = cur->next;
find = true;
}
if(!find) {
newHead = pre = tmp;
break;
}
}
while(cur != NULL) {
while(cur->next != NULL && pre->next->val == cur->next->val) {
cur = cur->next;
}
if(pre->next == cur) {
pre = cur;
} else {
pre->next = cur->next;
}
cur = cur->next;
}
return newHead;
}
};