4.浮点数二分【求数的平方根】

模板

public class BinarySearch {// 检查x是否满足某种性质public static boolean check(double x) {// 实现具体的检查逻辑return false; // 这里仅为示例，实际根据需求修改}public static double bsearch_3(double l, double r) {final double eps = 1e-6;   // 精度要求while (r - l > eps) {double mid = (l + r) / 2;if (check(mid)) {r = mid;} else {l = mid;}}return l;}public static void main(String[] args) {double result = bsearch_3(0, 100);  // 示例调用System.out.println("结果: " + result);}
}

例题：求数的平方根

package base;import java.util.Scanner;public class Sqrt_demo {public static void main(String[] args) {Scanner sc = new Scanner(System.in);//求x的平方根double x = sc.nextDouble();sqrt(x);}public static void sqrt(double x){double l =0,r = x;while (r-l>1e-8){double mid = (l+r)/2;if (mid*mid>x) r=mid;else l = mid;}System.out.println(String.format("%.6f",l));}
}