203. Remove Linked List Elements
Given the head
of a linked list and an integer val
, remove all the nodes of the linked list that has Node.val == val
, and return the new head.
Example 1:
Input: head = [1,2,6,3,4,5,6], val = 6 Output: [1,2,3,4,5]
Example 2:
Input: head = [], val = 1 Output: []
Example 3:
Input: head = [7,7,7,7], val = 7 Output: []
Constraints:
- The number of nodes in the list is in the range
[0, 104]
. 1 <= Node.val <= 50
0 <= val <= 50
Solution in C++
/**
* 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) {
ListNode* temp=head;
ListNode* ans;
if(head==NULL){
return NULL;
}
while(temp->val==val){
if(temp->next==NULL){
return NULL;
}
temp=temp->next;
}
ans=temp;
while(temp->next!=NULL){
if(temp->next->val==val){
ListNode* left=temp;
while(temp->next->val==val){
temp=temp->next;
if(temp->next==NULL){
left->next=NULL;
return ans;
}
}
left->next=temp->next;
}
else{
temp=temp->next;
}
}
return ans;
}
};
0 Comments
If you have any doubts/suggestion/any query or want to improve this article, you can comment down below and let me know. Will reply to you soon.