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Start date: Nov. 20, 2021, 5 p.m. UTC
Given a string consisting of characters 'a', 'b' and/or '?', replace each '?' with 'a' or 'b' so that the longest fragment of the resulting string consisting of equal letters is as short as possible.

Codility Developer Training - Challenge Everything!

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 $20 Steam Gift Card. Whether you fancy more skins and items for your hero in your favorite game or want to play something new - we’ve got you covered.

Once the Gamer’s Challenge has ended (on December 4th), 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!!

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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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1957 started 89 silver awards 112 golden awards

Hall of fame:

Kevin Sun
Time: 8 minutes
Albert Gutowski
Time: 13 minutes
nuip qiun
Time: 15 minutes