You have to write a function with the same name as the starter code. You can hit the reset button on the bottom of the trainer to get back the starter code, but it will delete any code that you have written. On codewars, the tests call your function directly and they pass in parameters as function arguments. You don't need to use input, and if you do, it will cause the tests to time out because nothing will ever be input into stdin. Also, printing the result will have no effect. The tests do not read the contents of stdout. The tests expect your function to return a value.