import java.util.Scanner; // 注意类名必须为 Main, 不要有任何 package xxx 信息 public class Main { public static void main(String[] args) { Scanner sc = new Scanner(System.in); double x = sc.nextDouble(); double value = cal(x); System.out.println(String.format("%.1f", value)); } private static double cal(double x) { double left = -20; double right = 20; double mid = 0; while (Math.abs(right - left) > 0.01) { mid = (left + right) / 2; if (mid * mid * mid > x) { right = mid; } else { left = mid; } } return mid; } }