How to Write a Custom Comparator in Python
Generally, you want to use the built-in sorted() function which takes a custom comparator as its parameter. We need to pay attention to the fact that …
Technical Articles
In-depth guides, insights, and best practices for modern software engineering
How to delete an AWS WAF – Web ACL
Usually, it’s quite easy to delete an AWS WAF, or Web ACL. But sometimes you may come across the following error when attempting to delete the …
Read Article →How to Sort an Integer in Python
Let’s say that you have an integer with value of 9271 and you want to sort it either ascending(1279) or descending(9721).
How would you do this …
Read Article →How to Upgrade PIP
In this tutorial, you will learn how to upgrade PIP.
You will also learn how to check the current version of PIP, as well as downgrade to a previous …
Read Article →How to Copy a File in Python
In this tutorial, you will learn how to copy a file using Python from a directory to another directory, or if you’re on Windows, then from a …
Read Article →Conway’s Game of Life – Unlimited Edition – in Python
What is this?
Read Article →Conways’s Game Of Life is a Cellular Automation Method created by John Conway. This game was created with Biology in mind but …
Most frequently used words in a text with Python
The challenge
Write a function that, given a string of text (possibly with punctuation and line-breaks), returns an array of the top-3 most occurring …
Read Article →The SongDecoder Dubstep Challenge with Java
The challenge
Polycarpus works as a DJ in the best Berland nightclub, and he often uses dubstep music in his performance. Recently, he has decided to …
Read Article →Break camelCase Challenge in Java
The challenge
Complete the solution so that the function will break up camel casing, using a space between words.
Example …
Read Article →Sort Binary Tree by Levels using Python
The challenge
You are given a binary tree:
class Node:
def __init__(self, L, R, n):
self.left = L
self.right = R …How to Split a String with Python
Splitting a string in Python is really easy.
You simply take a string and apply the split() method.
"Your String".split()
See some examples …
Read Article →How to fix the Terraform stuck on “Refreshing state…” problem
Terraform is a fantastic tool to help automate your infrastructure as code.
Quite a few times however, I have noticed a few strange issues, one of …
Read Article →The “Split Strings” Challenge using Java
The challenge
Complete the solution so that it splits the string into pairs of two characters. If the string contains an odd number of characters then …
Read Article →Converting to PigLatin with Python
The challenge
Move the first letter of each word to the end of it, then add “ay” to the end of the word. Leave punctuation marks …
Read Article →Solving the “Double Cola” Challenge using Java
The challenge
Sheldon, Leonard, Penny, Rajesh and Howard are in the queue for a “Double Cola” drink vending machine; there are no other …
Read Article →Convert Seconds to Human Readable Time (HH:MM:SS) using Java
The challenge
Write a function, which takes a non-negative integer (seconds) as input and returns the time in a human-readable format (HH:MM:SS)
HH= …
Solving the “Mexican Wave” Challenge using Java
The challenge
Task
Your task is to create a function that turns a string into a Mexican Wave. You will be passed a string and you must return that …
Read Article →Multiples of 3 and 5 with Python
The challenge
This multiples of 3 and multiples of 5 challenge is a variation of the common FizzBuzz question.
If we list all the natural numbers …
Read Article →Solving the “Catching Car Mileage Numbers” Challenge using Python
The challenge
Read Article →"7777…8?!??!", exclaimed Bob, "I missed it again! Argh!" Every time there's an interesting number coming up, he notices …
Counting smiley faces with Python
The challenge
Given an array (arr) as an argument complete the function countSmileys that should return the total number of smiling faces.
Rules for a …
Read Article →Convert String to Camel Case using Java
The challenge
Complete the method/function so that it converts dash/underscore delimited words into camel casing. The first word within the output …
Read Article →How to Setup an SSH Server on AWS
Basic instructions on how to set up an SSH server on an Ubuntu 16.04/18.04 EC2 instance.
Step 1 – Create a New User
sudo adduser testuser
Step 2 – …
Read Article →How to Convert Numeric Words into Numbers using Python
Challenge
Using Python, we want to convert words into numbers. In this challenge, we will explore how to convert a string into an integer.
The strings …
Read Article →Solve The Triangle of Odd Numbers using Python
The challenge
Given the triangle of consecutive odd numbers:
1
3 5
7 9 11
13 15 17 19
21 23 …