Delete node in a linked list问题
Delete Node in a Linked List问题
This is a LeetCode question, I knew its solution, but wondering about why my code not work.
Write a function to delete a node (except the tail) in a singly linked list, given only access to that node.
Supposed the linked list is 1 -> 2 -> 3 -> 4 and you are given the third node with value 3, the linked list should become 1 -> 2 -> 4 after calling your function
At first glance, my intution is delete like an array:
shift all the node values one front, then delete the tail, here's my implementation and test case:
class ListNode(object):
def __init__(self, x):
self.val = x
self.next = None
node1 = ListNode(1)
node2 = ListNode(2)
node3 = ListNode(3)
node4 = ListNode(4)
node5 = ListNode(5)
node1.next = node2
node2.next = node3
node3.next = node4
node4.next = node5
def deleteNode(node):
"""
:type node: ListNode
:rtype: void Do not return anything, modify node in-place instead.
"""
while node.next:
node.val = node.next.val
node = node.next
node = None
deleteNode(node4)
But After deletion, it has two 5 value nodes, the tail was still kept, can anyone please explain to me what's wrong here?
deleteNode(node4)
node1.val
Out[162]: 1
node1.next.val
Out[163]: 2
node1.next.next.val
Out[164]: 3
node1.next.next.next.val
Out[165]: 5
node1.next.next.next.next.val
Out[166]: 5
Really appreciate any help.
