My completed challenges for the websites: HackerRank, Kattis, and Project Euler.
The languages used throughout the challenges include: Ada, Assembly x86, BrainFuck, C, C#, C++, Dart, Java, Linux x86-64 Assembly, Ruby, Rust, Python, PowerShell and Swift.

Completed Challenge Name	Language	🔗
Hello World	C
Welcome to Java!	Java
Java Stdin and Stdout I	Java
Java If-Else	Java
Java Stdin and Stdout II	Java
Java Output Formatting	Java
Java Loops I	Java
Java Loops II	Java
Java Datatypes	Java
Java End-of-file	Java
Java Int to String	Java

Challenge Name	Language	🔗
Aaah	C, C++, C#, Java, PowerShell, Python
ABC	C, C++, Java
Add Two Numbers	C++
Akcija	C++, Java
Alphabet Spam	C++, C#, Java, Python
Apaxiaaaaaaaaaaans	Java
Autori	C++, Java
Avion	C++
Beavergnaw	C, C++, C#, Python
Bijele	Java
Cetvrta	Java
Chanukah Challenge	C++
ColdPuter Science	C++, Java
Count the Vowels	Python
Cryptographers Conundrum	C++, Java
Datum	Python
Detailed Differences	C++, Java
Dice Cup	C, C++, C#, Java, Python
Digit Swap	C++
Echo Echo Echo	C, C++, Java
Electrical Outlets	C++
Encoded Message	C++, Java
Everywhere	Java
Faktor	Java
Filip	Java
Finding An A	C++
FizzBuzz	C++, Java
FYI	C++
Grass Seeds Inc	Java
Greetings!	C++
Hanging Out on the Terrace	Java
Heart Rate	C, C++, Java, Python
Hello World	Ada, Assembly x86, BrainFuck, C, C++, C#, Dart, Go, Java, Linux x86-64 Assembly, PowerShell, Python, Ruby, Rust, Swift
Hissing Microphone	Java
International Dates	Python
Is It Halloween	Java
Janitor Troubles	Python
Jack-O'-Lantern Juxtaposition	C++
Judging Moose	C++, Java
Knight Packing	C++
Kornislav	C++, C#, Java, Python
Ladder	Java
Laptop Sticker	C++
Last Factorial Digit	C++, Java
Metronome	C++, Python
N-sum	C++
Nasty Hacks	Java
Number Fun	C++, Java
Oddities	Java
Odd Echo	C++
One Chicken Per Person	C++
Parking	C++, Java
Pet	Java
Piece of Cake	C++
Planina	C++, C#, Java, Python
Poker Hand	Java
Pot	Java
Problem E Drinking Song	C++, Dart
Provinces and Gold	C++
Qaly	Java
Quadrant Selection	C, C++, Dart, Java, PowerShell, Python, Rust
R2	C++, Java
Railroad	C++
Relocation	C++, Java
Reverse	C++
Reversed Binary Numbers	Java
Seven Wonders	C++, Java
Sibice	Java
Sok	Java
Solving for Carrots	C++, Java
Spavanac	C++, Java
Speed Limit	C++
Stuck in a Time Loop	C++, Java
Take Two Stones	C++, Java, PowerShell
Tarifa	C++, Java
Trik	C++, Java
Triangle Area	C++
Two Sum	C++
Which is Greater?	C++

Completed Challenge Name	Language	🔗
Even Fibonacci Numbers	C++
Largest Palindrome Product	C#
Largest Prime Factor	C#
Multiples Of 3 And 5	C++
Smallest Multiple	C#
Sum Square Difference	C#