{"id":"counter-subtraction-drops-nonpositive","text":"`Counter.__sub__` discards keys with zero or negative counts; an empty result after `A - B` means `A` is a sub-multiset of `B`.","truth_value":"IN","source":"entries/2026/06/06/ransom-note-solution.md","source_url":"","source_hash":"","justifications":[],"dependents":["counter-subtraction-is-multiset-containment-test","counter-universal-frequency-primitive"],"metadata":{},"created_at":"","updated_at":"","reviewed_at":"","verified_at":"","retracted_at":"","explanation":{"steps":[{"node":"counter-subtraction-drops-nonpositive","truth_value":"IN","reason":"premise"}]}}