Write a Java program to ask the user to a string and then invoke a recursive method you will define to tell the user if the input string is in set. L = {A^n$B^n: where A^n = AA... A (there are n copies of A), B^n = BB .... B (there are n copies of B, and n greaterthanorequalto 0.When n = 0, both A^n and B^n are empty strings}