Remove linked list elements
# Definition for singly-linked list.
# class ListNode:
# def __init__(self, val=0, next=None):
# self.val = val
# self.next = next
class Solution:
def removeElements(self, head: Optional[ListNode], val: int) -> Optional[ListNode]:
dummy = ListNode()
dummy.next = head
prev, curr = dummy, head
while curr:
if curr.val == val:
prev.next = curr.next
else:
prev = curr
curr = curr.next
return dummy.next
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 <= 500 <= val <= 50