The `triangle` exercise still has an old, unused, custom exception in its [example](https://github.com/exercism/csharp/blob/master/exercises/triangle/Example.cs) and [stub file](https://github.com/exercism/csharp/blob/master/exercises/triangle/Triangle.cs). These should be removed.
The
triangleexercise still has an old, unused, custom exception in its example and stub file. These should be removed.