{"id":"frozenset-as-grouping-key","text":"`frozenset(word)` is used as a hashable dictionary/Counter key to group strings by their distinct character sets, enabling O(n) grouping instead of O(n^2) pairwise comparison for set-equality predicates.","truth_value":"IN","source":"entries/2026/06/06/count-pairs-of-similar-strings-solution.md","source_url":"","source_hash":"","justifications":[],"dependents":[],"metadata":{},"created_at":"","updated_at":"","reviewed_at":"","verified_at":"","retracted_at":"","explanation":{"steps":[{"node":"frozenset-as-grouping-key","truth_value":"IN","reason":"premise"}]}}