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Analytics: Longest Unique Session Window
Also known as: Longest Substring Without Repeating Characters
I jump the left edge straight past the duplicate instead of stepping it. One pass, and the window never revisits a character.
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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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