Status: IN
The dominant two-phase algorithmic pipeline is: build a hash structure (Counter for frequencies, set for membership) in O(n) preprocessing, then consume it via single-pass streaming with O(1) accumulators — combining the repo's two most pervasive patterns into one archetypal shape.
Hash preprocessing (depth-2) feeds into single-pass streaming (depth-2); many solutions follow exactly this two-phase structure where the hash lookup enables the streaming pass to run in O(1) per element
Depends on (SL): hash-preprocessing-universal-first-step, single-pass-streaming-dominant-shape