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16 worked problems

Sliding Window

A moving range that grows and shrinks. The question asks about a contiguous range whose validity changes predictably as either edge moves.

Recognition signal

When should you think of Sliding Window?

The question asks about a contiguous range whose validity changes predictably as either edge moves.

Core invariant

What must stay true?

The current window and its frequency or aggregate state stay synchronized.

Practice in a deliberate order

Starter

Build the template

  1. #643 Maximum Average Subarray IEasy
Core

Recognize variations

  1. #3 Longest Substring Without Repeating CharactersMedium
  2. #209 Minimum Size Subarray SumMedium
  3. #340 Longest Substring with At Most K Distinct CharactersMedium
  4. #424 Longest Repeating Character ReplacementMedium
  5. #438 Find All Anagrams in a StringMedium
  6. #567 Permutation in StringMedium
Stretch

Combine ideas under pressure

  1. #76 Minimum Window SubstringHard
  2. #239 Sliding Window MaximumHard
  3. #992 Subarrays with K Different IntegersHard

What to learn in this cluster

  1. 01Fixed-size windows
  2. 02Variable windows with one constraint
  3. 03Frequency windows and monotonic deques

All Sliding Window problems

16 of 16 walkthroughs
Continue the cluster

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