code: private void defaultHeuristic() {
          IntStrategy intStrat = Search.intVarSearch(new FirstFail(csp), new IntDomainMin(), csp.retrieveIntVars(true));
          SetStrategy setStrat = new SetStrategy(csp.retrieveSetVars(), new InputOrder<>(csp), new SetDomainMin(), true);
          RealStrategy realStrat = new RealStrategy(csp.retrieveRealVars(), new Occurrence<>(), new RealDomainMiddle());
          solver.setSearch(new StrategiesSequencer(intStrat, realStrat, setStrat));
      }
docs: A naive heuristic to be sure every variables will be instantiated.