Status: IN
The hash-then-stream pipeline's universal scope is demonstrated by two complementary exemplar families: palindrome problems exercise Counter's full multiset algebra for aggregate frequency-parity reduction, while Two Sum problems exercise point-lookup semantics through hash map complement queries — together covering both fundamental query modes (aggregate frequency and exact membership) of the hash preprocessing phase.
complementary exemplars demonstrate coverage of both aggregate and point query modes of the hash phase
Depends on (SL): palindrome-instantiates-hash-then-stream, two-sum-family-spans-lookup-strategy-space