One line solution [Swift]
\n# Code\n\nclass Solution {\n    func smallestEvenMultiple(_ n: Int) -> Int {\n        n.isMultiple(of: 2) ? n : n * 2\n    }\n}\n
\n# Code\n```\nclass Solution {\n    func smallestEvenMultiple(_ n: Int) -> Int {\n        n.isMultiple(of: 2) ? n : n * 2\n    }\n}\n```
['Swift']