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Pair a Coder

Start date: Jan. 22, 2022, 5 p.m. UTC
Given a string, calculate the length of the shortest string which can be achieved by removing any number of substrings that start and end with the same letter.

Yer a coder, Harry!

Please remember that you aren’t allowed to use magic outside of Hogwarts, so to win this challenge, you’ll need to rely only on your coding skills.

The first 3 developers to solve the challenge perfectly in the least amount of time from the start of the challenge will be added to the Codility Hall of Fame and win a $25 Netflix gift card so that you can rewatch your favorite movie series - on us!

Once the Pair a Coder challenge has ended (on February 5th), you will still be able to take the challenge and gain certificates, but you will no longer be in the running for prizes.

Good luck solving this challenge! Mischief managed!

About Codility

We help engineering leaders hire great software developers into their teams by evaluating technical skills in an unbiased way. We’re committed to levelling the playing field by building a platform that provides equal opportunity to all developers worldwide. Interested in joining us? We’re currently hiring engineers to work remotely from all over Europe.

The challenge is now over, but you may still practice on this task. Below, you can also find a video with explanation of possible solutions for the task:

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2577 started 188 silver awards 90 golden awards

Hall of fame:

Kerim Kochekov
Time: 6 minutes
乐平 汪
Time: 8 minutes
Aryan C403
Time: 12 minutes