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hardBlind 75

Minimum Window Substring

Minimum Window Substring is the sliding window pattern: grow, shrink, and maintain just enough state to stay linear. It's a hard one for a reason: it stresses stateful scanning when the rules pile up. Once your window update rules are consistent, you get linear time almost for free.

Arrays & HashingSliding WindowString

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Sliding Window Algorithm

Sliding window processes arrays or strings by moving a window through the data, updating results incrementally instead of recalculating from scratch. Reach for it when you see "contiguous subarray," "longest/shortest substring," or "at most K distinct."

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