Abstract out the mapping itself, and then apply the composed transformation from map1 and map2 to it. map1 and map2 don't need to do any looping themselves, jus

Abstract out the mapping itself, and then apply the composed transformation from map1 and map2 to it. map1 and map2 don't need to do any looping themselves, just work take an int and return an int. Think of it in terms of doing all of your transformations in one pass, if that helps.