The Monster Parade

Catch the longest run with no monster twice.

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How to beat it

Stretch the window right one monster at a time. The moment a repeat walks in, shrink from the left until the old copy leaves. Each monster enters once and leaves once.

Now the real boss

Interviews ask for the code. Watch it run, then write it yourself, tested in Python, C++ or Java.

Watch the guide Solve Longest Substring Without Repeating Characters

On your phone? Writing code is easier on a laptop: open bossfight.dev/problems/longest-substring-without-repeating-characters there. Sign in with GitHub to keep your progress on every device.

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