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The Anagram Lenses

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Problem context and objectives
Mission briefing

Live-ops game engineer · A multiplayer arena is reporting bursts of lag

Find the smallest or strongest contiguous time window: The Anagram Lenses.

Scanning the entire history after every event cannot keep up with live players.

How you win

  1. 1Recognize when Frequency signature window matches the clues
  2. 2Keep this true after every move: the window frequency table describes exactly pattern.length characters
  3. 3Reach the result within O(n)

Rules and pressure

  • Target cost: O(n)
  • State rule: the window frequency table describes exactly pattern.length characters
Lesson 1 of 3

Build the pattern frequency inventory once. Then slide an equally wide lens and compare counts.

Your call · Do abc and cba match?

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