{"id":"diff-tuple-hashable-for-counter","text":"The difference array in `odd-string-difference` is returned as a tuple (not list) specifically so it can be used as a `Counter` key — switching to list would break the frequency counting","truth_value":"IN","source":"entries/2026/06/06/odd-string-difference-solution.md","source_url":"","source_hash":"","justifications":[],"dependents":[],"metadata":{},"created_at":"","updated_at":"","reviewed_at":"","verified_at":"","retracted_at":"","explanation":{"steps":[{"node":"diff-tuple-hashable-for-counter","truth_value":"IN","reason":"premise"}]}}