Java Fastest solution 0ms Runtime O(1) Space(1) 1 line code
\nclass Solution {\n    public int smallestEvenMultiple(int n) {\n        return n%2==0?n:n*2;\n    }\n}\n
```\nclass Solution {\n    public int smallestEvenMultiple(int n) {\n        return n%2==0?n:n*2;\n    }\n}\n```
['Java']