Now a day's most of the companies are following the Online Coding Test before conducting an interview with candidates. This will get helps to Employers to find candidates who have good coding skills. As a candidate, I have taken a few of the online coding tests as part of getting a job. Sometimes I have felt hard to complete all the coding challenges within a given time limit. Even though I have cleared a few of the tests with a good score of around 80%. Few of the challenges, which I remember I am placing here. So, this will help me next time when I am taking tests and others too.
Codility division sequence challenge
Remove duplicate from String without using Collection API

Interview Questions:

Wells Fargo Java Interview Questions
Install Docker for Windows
Steps to Build and Run a project in Docker
Build problems with Windows Containers in Docker
Docker Kitematic installation
Jenkins setup from Docker Kitematic 
Open browser with URL using Java program

I would like to request you, please write the challenge which you have faced in the comments. Thanks for visiting. Happy Learning...:)