1.代码如下：
package com.aaa;import java.util.Scanner;public class Shuzi {public static void main(String[] args) {
// 求数字的绝对值Scanner sc=new Scanner(System.in);while (true) {System.out.println("请输入你要判断的数字");double a = sc.nextDouble();if (a >= 0) {a = a;} else if (a < 0) {a = -a;}System.out.println("您输入的数字的绝对值为：" + a);}}
}
2. 运行结果图如下：
