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Remove Linked List Elements - Linked List - Easy - LeetCode - MiniTV

Remove Linked List Elements - Linked List - Easy - LeetCode - मिनी टीवी

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

Example:

Input:  1->2->6->3->4->5->6, val = 6
Output: 1->2->3->4->5

/**
 * Definition for singly-linked list.
 * public class ListNode {
 *     public int val;
 *     public ListNode next;
 *     public ListNode(int val=0, ListNode next=null) {
 *         this.val = val;
 *         this.next = next;
 *     }
 * }
 */
public class Solution {
    public ListNode RemoveElements(ListNode head, int val) {
        ListNode temp = head;        
        if(head == null){
            return head;
        }
        
        if(head.next == null){
            if(head.val==val){
                return null;
            }
            return head;
        }
        
        while(temp.next!=null){
            if(temp.next.val==val){
                temp.next = temp.next.next;
            }
            else{
                temp = temp.next;
            }
        }
        
        //check if first node is having given value
        if(head.val==val){
            head = head.next;
        }
        
        return head;
    }
}

Time Complexity: O(n)

Space Complexity: O(1)