For this question, we will be focusing on the LRU (Least Recently Used) and LFU (Least Frequently Used) page-replacement algorithms.

a) For implementation, how could a hash table or a doubly linked list be utilized for these page-replacement algorithms?

b) Using your answer from Part a, explain the differences, for implementation, between LFU and LRU for adding new pages! (Hint: Think about the policies for both.)