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 in = new Scanner(System.in); // 注意 hasNext 和 hasNextLine 的区别 while (in.hasNextDouble()) { // 注意 while 处理多个 case double a = in.nextDouble(); double left = Math.min(a, -1); double right = Math.max(a, 1); double mid = 0.0; while((right - left) > 0.001){ mid = left + (right - left)/2; if(mid * mid * mid > a){ right = mid; }else if(mid * mid * mid < a){ left = mid; }else{ System.out.print(mid); } } System.out.printf("%.1f",right); } } }