leetcode——Remove Duplicates from Sorted List II 删除排序字符串中反复字符(AC)
Given a sorted linked list, delete all nodes that have duplicate numbers, leaving only distinct numbers from the original list.
For example,
Given 1->2->3->3->4->4->5
, return 1->2->5
.
Given 1->1->1->2->3
, return 2->3
.
没什么太多讲的,能够使用递归和迭代两种方法来做,要细致考虑各种输入情况。code例如以下:
class Solution { public: ListNode *deleteDuplicates(ListNode *head) { if(head == NULL) return NULL; ListNode *first = head,*second = NULL,*result = NULL; bool isDup = false; while(first!=NULL) { isDup = false; while(first->next != NULL && first->val == first->next->val) { isDup = true; first = first->next; } if(!isDup) { if(second == NULL) { second = first; if(result == NULL) result = second; } else { second->next = first; second = second->next; } } first = first->next; } if(second!=NULL) second->next = NULL; return result; } };