Code the problem in scheme. Make use you test it and follows the requirement:

0. Write the following function using call/cc and a single helper function that uses "normal" recursion instead of tail recursion. xindex takes an atom and a list containing sublists. The output list should be the same as the input list except that any sublist (including the main list) that contains the given atom should be emptied of all contents (atoms, lists, etc.), and instead, the only content of that sublist should be the index of the first occurrence of the atom in that list