Write a function to delete a node (except the tail) in a singly linked list, given only access to that node.
Given linked list – head = [4,5,1,9], which looks like following:
Input: head = [4,5,1,9], node = 5 Output: [4,1,9] Explanation: You are given the second node with value 5, the linked list should become 4 -> 1 -> 9 after calling your function.
Input: head = [4,5,1,9], node = 1 Output: [4,5,9] Explanation: You are given the third node with value 1, the linked list should become 4 -> 5 -> 9 after calling your function.
- The linked list will have at least two elements.
- All of the nodes’ values will be unique.
- The given node will not be the tail and it will always be a valid node of the linked list.
- Do not return anything from your function.
- The problem only provided the node, not head node, so we can’t traverse the linked list to find the node to delete.
- An easy way to solve is to replace the node’s current value with the next node value
Below is the white board:
class LN: def __init__(self, val): self.val = val self.next = None class Sol: def deleteNode(self, node): if node is not None: delnode = node.next node.val = delnode.val #find the next node to replace/delete if delnode.next is not None: node.next = delnode.next else: node.next = None node = None
- Time complexity is O(1), space complexity is O(1) as well