How to Create an S3 bucket with PublicRead in CloudFormation
Here’s a minimal CloudFormation template for creating an S3 bucket with public read access. This is useful for hosting static assets like …
Read Article →Technical Articles
In-depth guides, insights, and best practices for modern software engineering
How to Create a VPC in CloudFormation
It’s very easy to deploy a VPC using CloudFormation:
AWSTemplateFormatVersion: 2010-09-09
Description: Deploy a VPC
Resources:
VPC:
Type: …How to Setup Git on EC2 for AWS CodeCommit
Connect to the instance:
chmod 400 KEYPAIR.pem
ssh -i KEYPAIR.pem ec2-user@EC2PublicIP
Install Git:
sudo yum install -y git
Setup Git Credential …
Read Article →The Difference of 2 in Java
The challenge
The objective is to return all pairs of integers from a given array of integers that have a difference of 2.
The resulting array should …
Read Article →How to Make the Deadfish Swim in Java
The challenge
Write a simple parser that will parse and run Deadfish.
Deadfish has 4 commands, each 1 character long:
iincrements the value …
How to Write Number in Expanded Form in Java
The challenge
You will be given a number and you will need to return it as a string in Expanded Form.
Examples:
Challenge.expandedForm(12); // Should …Is a Number Prime in Java
The challenge
Define a function that takes one integer argument and returns a logical value true or false depending on if the integer is a prime.
Per …
Read Article →How to Calculate Minutes to Midnight in Java
The challenge
Write a function minutesToMidnight(d) that will take a date object as the parameter. Return the number of minutes in the following …
Read Article →How to Change the Timestamp of a File on Mac/Linux
If you have a file on your machine, and you want to change the created/modified time/date stamp, then you can use the touch command.
touch -t …How to Round up to the Next Multiple of 5 in Python
The challenge
Given an integer as input, can you round it to the next (meaning, “higher”) multiple of 5?
Examples:
input: output:
0 …How to get the Sum of the First nth Term of a Series in Java
The challenge
Your task is to write a function that returns the sum of the following series up to nth term(parameter).
Series: 1 + 1/4 + 1/7 + 1/10 + …How to satisfy Wilson Primes in Python
The challenge
Wilson primes satisfy the following condition. Let P represent a prime number.
Then ((P-1)! + 1) / (P * P) should give a whole number. …
How to Boot an EC2 with a WebServer Setup
Create a new AWS EC2 instance, and set the User Script to the following:
This is handy for quick demos or testing — the instance comes up with Apache …
Read Article →Writing a Sleigh Authentication in Python
The challenge
Christmas is coming and many people dreamed of having a ride with Santa’s sleigh. But, of course, only Santa himself is allowed to …
Read Article →Solving for Multiple of Index in Python
The challenge
Return a new array consisting of elements which are multiple of their own index in input array (length > 1).
Examples:
[22, -6, 32, …
Read Article →How to Find an item’s Alphabet Position in Python
The challenge
When provided with a letter, return its position in the alphabet.
Input :: “a”
Ouput :: “Position of alphabet: …
Read Article →How to Keep up the Hoop in Java
The challenge
Alex just got a new hula hoop, he loves it but feels discouraged because his little brother is better than him
Write a program where …
Read Article →Will there be Enough Space in Java
The challenge
Bob is working as a bus driver. However, he has become extremely popular amongst the city’s residents. With so many passengers …
Read Article →How to Swap Node Pairs In Linked List in Java
The challenge
If you are given the head node in a linked list, write a method that swaps each pair of nodes in the list, then returns the head node of …
Read Article →How to Solve ‘Finding Neo’ in Java
The challenge
Neo is somewhere in the Matrix.
public interface Matrix {
public int size();
public int get(int x, int y);
}
You are Morpheus, and …
Read Article →How to Solve a Pandigital Sequence in Java
The challenge
In mathematics, a pandigital number is a number that in a given base has among its significant digits each digit used in the base at …
Read Article →How to get Meta-Data information from an AWS EC2 Instance
If you need to query meta-data information from your running EC2 instance, you can curl the following location:
curl …How to write a Lazy Repeater Helper in Python
The challenge
The make_looper() function takes a string (of non-zero length) as an argument. It returns a function. The function it returns will …
How to write a String Case Conversion Helper in Python
The challenge
In this challenge, you will make a function that converts between camelCase, snake_case, and kebab-case.
You must write a function that …
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