Write a program that prints the question "Do you want to continue?" and reads a user input. If the user input is "Y", "Yes", "OK", "Sure", or "Why not?", print out "OK". If the user input is "N" or "No", then print out "Terminating." Otherwise, print "Bad input." The case of the user input should not matter. For example, "y" or "yes" are also valid inputs. Write a class InputChecker for this purpose.