A detailed examination of the Floyd cycle detection algorithm in Ruby — In our discussions of Data Structures and Algorithms in Ruby we have investigated Singly Linked Lists and applied some standard methods on them including #push, #pop, #shift, #unshift, #get, #set, #remove, and #reverse. See here and here for the two articles going through these methods. Odd as it may seem…

A simple algorithm coded in Ruby to find the next lexicographic permutation explained in detail. — What is a Lexicographic Permutation? A permutation of a string or integer refers to the possible arrangements of the characters or numerals within the set. For example, “ab” has two permutations: “ab” and “ba.” A lexicographic permutation is a list of all possible permutations of a set in increasing numeric…

A warning to freelancers — Taylor (not their real name) received an email indicating someone sent them a message on LinkedIn. “I hadn’t logged onto LinkedIn in a while,” Taylor told me. “When I checked it out, it was someone requesting my services as a ghostwriter.” Taylor and I began to use LinkedIn during the…

I am going to start off by saying that this is the fastest searching algorithm with a few caveats. For starters, the data structure that is being search through needs to be sorted. Also, there are some nuances regarding some other algorithms that may search quicker depending on how evenly…

We have now come of the final of the three main types of Depth-First Search (DFS) for a Binary Search Tree: In-Order traversal. …

Last week we introduced the concept of Depth-First Search for Binary Tree traversals. Of the three main types of Depth-First Search (DFS) algorithms, we began with a pre-order search, which begins at the root node of the binary tree and returns each node visited on the way down the left…

In continuing with our current topic of binary tree traversals in Ruby, we are going to introduce depth-first search this week. If you recall from the last article on breadth-first search, a traversal through a binary tree should be accomplished by visiting each node on the tree only once. That…

Last week, we implemented a #find method for our Binary Search Tree which returned the Boolean true/false indicating whether our value was found or not. What if we wanted to return all the nodes in our Binary Search Tree? Look at a representation of any Binary Tree (it doesn’t even…

…and, an introduction to recursion methods — Last week we began our introduction into the binary search tree. In Ruby, we set-up our Node Class and our BinarySearchTree Class and implemented the #insert method. Today, we are going to code the #find method which will give us some better insight into how a binary search tree is…