Lowest Common Ancestor (BST)

The Binary Search Tree (BST) is a tree like data structure that allows for the quick lookup of data. They work by storing inserted data in a tree like structure that uses the “divide and conquer” approach to locate data. Each node in the tree has, at most, two children. The left hand side (lhs) node will always contain a value that is less than it’s parent. The right hand side (rhs) node will always contain a value that is greater-than or equal to it’s parent.

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LRU Cache Implementation

One of the problems any developer will eventually have to resolve is one of latency; specifically, being able to retrieve and process data in a timely fashion.  This issue can come in many guises but they generally manifest as needing to read data from a backing store that cannot deliver the high performance needed by the application. This can be a tricky problem to solve but the general method is to implement some form of caching. The remainder of this article will discuss one caching mechanism, called the LRU Cache.

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Reversing a linked list

Linked lists are an interviewers favourite subject matter. Whilst they are pretty easy to understand, at least in principle, they do require a little bit of brain warping to get your head around what’s going on under the hood. Of the common questions about linked lists I’ve come across, this quiz tackles the most common: how to reverse a linked list.

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