remove_node.cpp

//program to remove node from linked list
//problem link: https://leetcode.com/problems/remove-linked-list-elements/

/**
 * Definition for singly-linked list.
 * struct ListNode {
 *     int val;
 *     ListNode *next;
 *     ListNode() : val(0), next(nullptr) {}
 *     ListNode(int x) : val(x), next(nullptr) {}
 *     ListNode(int x, ListNode *next) : val(x), next(next) {}
 * };
 */
class Solution {
public:
    ListNode* removeElements(ListNode* head, int val) {

       if(head==NULL)
       {
           return head;
       }
       while(head->val==val)
       {
           head=head->next;
           if(head==NULL)
           {
               return head;
           }
       }
       ListNode*tmp=head;
       while(tmp!=NULL&&tmp->next!=NULL)
       {
           if(tmp->next->val==val)
           {
               tmp->next=tmp->next->next;
           }
           if(tmp->next!=NULL&&tmp->next->val!=val)
           {
               tmp=tmp->next;
           }
       }
       return head;
    }
};