auto.addTransition(start, start, 0, 1);
auto.addTransition(start, end, 2);
auto.addTransition(end, start, 2);
auto.addTransition(end, start, 0, 1);
solver.post(IntConstraintFactory.regular(vars, auto));
solver.set(IntStrategyFactory.lexico_LB(vars));
solver.findAllSolutions();