Dot-and-Star Pattern Matching
Asked at Citadel · Coding Questions · Difficulty: Hard · Last asked Dec 16, 2025
Write a small pattern matcher that supports two special symbols: a dot that stands for any one character, and a star that repeats the element before it. The pattern must describe the whole text, not just a part of it. This is the core of many simple filter languages (log filters, route matchers), and it has to be written by hand, without a regular-expression library.
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