Cache issue. You need to refresh the page after a while if this happens. If the issue still persists, you may reach out to [mods on discord(https://discord.com/invite/mSwJWRvkHA)

Your latest solution is wrong and is impossible to submit. Note that you do not need to change the function signature provided. Also, read this for info on how to train on Codewars

The ISSUE label is for provable kata issues. Please use the QUESTION label when asking a question and appropriate formatting when posting code. See https://docs.codewars.com/training/troubleshooting#post-discourse.

You don't need to do IO on codewars. See https://docs.codewars.com/training/troubleshooting/#.print-vs-return and https://docs.codewars.com/training/training-example/#writing-a-solution.

If your code is rejected, it's because your code doesn't do what it is asked. It's as simple as that.

See https://docs.codewars.com/training/training-example.

If you don't keep the data types and the method's name, then it won't work. The tests look for that. Normally initial code shouldn't make it more difficult for you. If you write your code in your IDE from scratch, then you have the extra work to adapt it to the initial code here.

Not a kata issue, please use the initial code and write your code inside it.

/* d - the days to rent */
unsigned rental_car_cost(unsigned d)
{
    return 0u;
}

Also, the input value is passed as the argument of that function, not read from the keyboard. Please read this: https://docs.codewars.com/getting-started/solving-kata

Please use appropriate formatting and mark your post as a spoiler when posting code. See https://docs.codewars.com/training/troubleshooting#post-discourse.

This article should help you get started on codewars: https://docs.codewars.com/training/training-example.