Scanner sc = new Scanner(System.in); while (sc.hasNext()){ double ddin = sc.nextDouble(); double dd = ddin>0? ddin : -ddin; double i = 0; while (dd-i*i*i>0.01){ i+=0.01; } String format = String.format("%.1f", i); if (ddin>0){ System.out.println(format); }else { System.out.println("-" +format); } }