Dariel invites you to take a programming test

1. There are 3 tasks in the test. You can solve them in any order.
2. There's no option to pause. Make sure you will not be interrupted for 20 minutes.
3. Do not use any ready-made solution(s). Cheating is easy for us to discover.
   Play the game. Read our Code of Honour.
4. Your solution(s) should consider all possible corner cases and handle large input efficiently. Passing the example test does not indicate that your solution is correct. The example test is not part of your final score.
5. After finishing the test you will receive feedback containing your score. See example feedback.
6. If you accidentally close your browser or tab before completing your test, please check your browser history to recover your started session.
7. Hint: you can use your own IDE and use copy-paste, but make sure your solution compiles in Codility's environment.

You can write your solution(s) in C, C++, C#, Go, Java, JavaScript, Lua, Objective-C, Pascal, Perl, PHP, Python, Ruby, Scala, Swift 4 or Visual Basic*. * the availability of the programming languages depends on the task, and in some tasks the choice of programming languages might be limited.