We're definitely not doing any "Leetcode style" interviews over here - these are basic "can you perform basic programming tasks as you've stated" type questions.
Not really, since failing FizzBuzz basically ends the interview.
That said, Pascal's and Non-Primes allows us to do a few minutes of basic, "that looks great, what are some ideas for optimizing it" work together once they have established that they have the basics of programming.
I am incredibly open to suggestion on better ways to evaluate people for both (a) their basic ability to code, and (b) their ability to think about code/optimization.