1. [6 points] Write a function (pseudocode) delete_key()that takes key x and deletes all occurrences of the given key x from the doubly linked list. What is the time complexity of your code? Consider the same Doubly Linked List class as defined during the lecture session.

Example:

Input: 2 <-> 4 <-> -3 <-> 8 <-> 2 <-> 2 <-> 9

Key: 2

Output: 4 <-> -3 <-> 8 <-> 9

Input: 5 <-> 5

Key: 5

Output: null

Input: 5 <-> 1 <-> 1 <-> 7

Key: 10

Output: 5 <-> 1 <-> 1 <-> 7