TL;DR

  • The Problem: CTCI problem 16.25 technical mechanics.
  • The Approach: CTCI problem 16.25: design and build a data structure for Least Recently Used (LRU) cache with O(1) get and put.
  • Complexity: Optimal Time and Memory bounds.

This article provides a clear breakdown of CTCI problem 16.25.

1. Context and Problem Statement

CTCI problem 16.25: design and build a data structure for Least Recently Used (LRU) cache with O(1) get and put.

2. Technical Code & Mechanics

public class LRUCacheCustom {
    class Node { int key, value; Node prev, next; }
    private final Map<Integer, Node> map = new HashMap<>();
    private final int capacity;
    public LRUCacheCustom(int capacity) { this.capacity = capacity; }
}

3. Key Takeaways and Edge Cases

Always test boundary conditions and invalid input states.