I am working on a homework assignment to create a function and it says to use a "pure recursive approach". I am trying to piece together what is actually meant by this. I am aware a recursive function calls it self, usually by reducing until it hits a base case and a pure function is basically a function that does not change the variable values.
I assume all that is meant by "pure recursive approach" is to use recursion that does not change the original values of the parameters out side of the function. Is there something I'm missing?