{"id":"max69-no-op-on-all-nines","text":"When `num` contains no 6s, the function returns the input unchanged because `str.replace` is a no-op when the target substring is absent — no special-case code needed.","truth_value":"IN","source":"entries/2026/06/06/maximum-69-number-solution.md","source_url":"","source_hash":"","justifications":[],"dependents":[],"metadata":{},"created_at":"","updated_at":"","reviewed_at":"","verified_at":"","retracted_at":"","explanation":{"steps":[{"node":"max69-no-op-on-all-nines","truth_value":"IN","reason":"premise"}]}}