Remove Linked List Elements &&remove-duplicates-from-sorted-list

Remove all elements from a linked list of integers, that has value val .

Sample Example

Given 1->2->3->3->4->5->3 , val = 3, you should return the list as1->2->4->5

The algorithm of the problem is very simple, if you encounter the element to be deleted, skip, directly find the next non-target element; but I have been to the list of links to the problem of such degradation, so also studied some time.

1 /**2 * Definition for singly-linked list.3 * public class ListNode {4 * int val;5 * ListNode Next;6 * ListNode (int x) {val = x;}7  * }8  */9  Public classSolution {Ten     /** One      * @paramhead a ListNode A      * @paramval an integer -      * @returna ListNode -      */ the      PublicListNode removeelements (ListNode head,intval) { -         //Write Your code here -ListNode Helpnode =NewListNode (0); -Helpnode.next =head; +ListNode p =Helpnode; -          while(P.next! =NULL){ +             if(P.next.val = =val) { AP.next =P.next.next; at             } -             Else { -p =P.next; -             } -         } -         returnHelpnode.next; in     } -}

Extension questions:

Delete a repeating element in a sorted listEasy To remove duplicate elements from the sorted list view Run results

Given a sorted list, delete all duplicate elements each element leaves only one

Sample Example

Give 1->1->2->null, return 1->2->null

Give 1->1->2->3->3->null, return 1->2->3->null

1 /**2 * Definition for ListNode3 * public class ListNode {4 * int val;5 * ListNode Next;6 * ListNode (int x) {7 * val = x;8 * next = null;9  *     }Ten  * } One  */ A  Public classSolution { -     /** -      * @paramListNode Head is the head of the linked list the      * @return: ListNode head of linked list -      */ -      Public StaticListNode deleteduplicates (ListNode head) { -ListNode p =NewListNode (0); +P.next =head; -         if(Head = =NULL ) +            return NULL; A          while(Head.next! =NULL){ at             if(Head.next.val = =head.val) { -Head.next =Head.next.next; -}Else{ -Head =Head.next; -              } -         } in         returnP.next; -     }   to}

Remove Linked List Elements &&remove-duplicates-from-sorted-list