题解 | #求解立方根#

import java.util.Scanner;
import java.text.DecimalFormat;

// 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);
        // 注意 hasNext 和 hasNextLine 的区别
        while (sc.hasNext()) { // 注意 while 处理多个 case
            Double d = sc.nextDouble();
            System.out.printf("%.1f",getResult(d));
        }
    }

    private static double getResult(double b) {
        boolean flag = true;
        if(b<0){
            b = - b;
            flag = false;
        }
        double mid =0.0,left=0.0,right=b; 
	  //当b小于1的时候，立方根比b大，但是比1小
        right = Math.max(b,1);
        while(right-left>0.01){
            mid = right - (right-left)/2;
            if(mid*mid*mid>b){
                right = mid;
            }else{
                left = mid;
            }
        }

        if(!flag){
            mid = -mid;
        }
        return mid;
    }
}