docs: public void mapInputToOutput(ValueNumber input, ValueNumber output) {
          BitSet inputSet = getInputSet(output);
          inputSet.set(input.getNumber());
          if (DEBUG) {
              System.out.println(input.getNumber() + "->" + output.getNumber());
              System.out.println("Input set for " + output.getNumber() + " is now " + inputSet);
          }
      }