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Minimum Interval to Include Each Query
Binary search is the tool here, but the real test is whether your invariant stays crisp. It's a hard one for a reason: it stresses boundary precision when the rules pile up. Interviewers care more about airtight boundaries than speed here.
Learn this pattern
Arrays and Hashing Interview Questions
Arrays and hashing problems are about fast lookup choices: set for membership, map for attached state, and buckets when counts are bounded. Reach for this family when brute force compares too many pairs or when you need to remember what you saw earlier in one pass.
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