pub fn slow_permutations(n: i32, k: i32) -> i32 {
  if k > n { panic!("Aaah! First parameter must be the larger number!") };
  factorial(arrayify(n)) / factorial(arrayify(n-k))
}

pub fn slow_combinatorial_count(n: i32, k: i32) -> i32 {
  if k > n { panic!("Aaah! First parameter must be the larger number!") };
  let m = arrayify(n);
  let vals = array_tool::uniques(
    m[arrayify(n-k).len()..m.len()].to_vec(),
    arrayify(k)
  );
  factorial(vals[0].to_vec()) / factorial(vals[1].to_vec())
}