題意
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.
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解法
保留一個pre指針,一個cur指針,比較兩個指針的值是否相等,刪除重複的節點
實現
/**
* 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 = head;
ListNode* cur = head->next;
while(cur != NULL){
if(cur->val == pre->val){
pre->next = cur->next;
cur->next = NULL;
cur = pre->next;
}else{
pre = cur;
cur = cur->next;
}
}
return head;
}
};