Simple linked list remove action
# Definition for singly-linked list.
# class ListNode:
# def __init__(self, x):
# self.val = x
# self.next = None
class Solution:
def removeElements(self, head, val):
"""
:type head: ListNode
:type val: int
:rtype: ListNode
"""
pointer = ListNode(-1)
pointer.next = head
previous = pointer
present = head
while present:
if present.val == val:
previous.next = present.next
else:
previous = previous.next
present = present.next
return pointer.next