code: private void addClauseSetWithRelaxation(final Variable relaxationVar, final Formula formula) {
          switch (formula.type()) {
              case TRUE:
                  break;
              case FALSE:
              case LITERAL:
              case OR:
                  this.addClauseWithRelaxation(relaxationVar, formula);
                  break;
              case AND:
                  for (final Formula op : formula) { this.addClauseWithRelaxation(relaxationVar, op); }
                  break;
              default:
                  throw new IllegalArgumentException("Input formula ist not a valid CNF: " + formula);
          }
      }
docs: Adds a formula which is already in CNF with a given relaxation to the solver.
  @param relaxationVar the relaxation variable
  @param formula       the formula in CNF