java实现简单数字程序

使用java 实现以下程序

(0) 输入一个新的数字 (当用户输入0时,让他输入一个新的数字)
(1) 找出最大的数字
(2) 计算和
(3) 计算range(最大的数减去最小的数)
(4) 计算平均
(5) 将输入的数字从小到大排列打印
(6) 退出.

输入你的选项:
输入三个数字:

还以为是沙发呢，哈哈，没关系，我也学习了！测试好几遍，没问题了，随便用

package cn.bdqn.demo02;

import java.util.Scanner;

public class NumDemo {

    public static void main(String[] args) {
        
        Scanner sc =new Scanner(System.in);
        
        //定义选项数字
        int num=0;
        //定义三个数字
        int num1=0,num2=0,num3=0;
        System.out.println("(0) 输入一个新的数字 ");
        System.out.println("(1) 找出最大的数字");
        System.out.println("(2) 计算和");
        System.out.println("(3) 计算range");
        System.out.println("(4) 计算平均");
        System.out.println("(5) 将输入的数字从小到大排列打印");
        System.out.println("(6) 退出");
        System.out.println("输入你的选项：");
        num=sc.nextInt();
        if (num==0) {
            //当用户输入0时,重新输入一个新的选项数字
            System.out.println("输入一个新的数字:");
            num=sc.nextInt();
        }
        if(num==6){
            System.out.println("退出");
        }else{
            System.out.println("输入三个数字:");
            System.out.print("第一个数字：");
            num1=sc.nextInt();
            System.out.print("第二个数字：");
            num2=sc.nextInt();
            System.out.print("第三个数字：");
            num3=sc.nextInt();
        }
        switch (num) {
        case 1:
            if(num1>num2&&num1>num3){
                System.out.println("最大的数字为:"+num1);
            }else if(num2>num1&&num2>num3){
                System.out.println("最大的数字为:"+num2);
            }else if(num3>num1&&num3>num2){
                System.out.println("最大的数字为:"+num3);
            }
            break;
        case 2:
            System.out.println("三个数字之和为："+(num1+num2+num3));
            break;
        case 3:
            if(num1>num2&&num1>num3){
                if(num2>num3){
                    System.out.println("最大的数减去最小的数range为:"+(num1-num3));
                }else{
                    System.out.println("最大的数减去最小的数range为:"+(num1-num2));
                }
            }else if(num2>num1&&num2>num3){
                if(num1>num3){
                    System.out.println("最大的数减去最小的数range为:"+(num2-num3));
                }else{
                    System.out.println("最大的数减去最小的数range为:"+(num2-num1));
                }
            }else if(num3>num1&&num3>num2){
                if(num1>num2){
                    System.out.println("最大的数减去最小的数range为:"+(num3-num1));
                }else{
                    System.out.println("最大的数减去最小的数range为:"+(num3-num2));
                }
            }
            break;
        case 4:
            System.out.println("三个数字均值为："+(num1+num2+num3)/3);
            break;
        case 5:
            if(num1>num2&&num1>num3){
                if(num2>num3){
                    System.out.println("数字从小到大排列为:"+num3+"<"+num2+"<"+num1);
                }else{
                    System.out.println("数字从小到大排列为:"+num2+"<"+num3+"<"+num1);
                }
            }else if(num2>num1&&num2>num3){
                if(num1>num3){
                    System.out.println("数字从小到大排列为:"+num3+"<"+num1+"<"+num2);
                }else{
                    System.out.println("数字从小到大排列为:"+num1+"<"+num3+"<"+num2);
                }
            }else if(num3>num1&&num3>num2){
                if(num1>num2){
                    System.out.println("数字从小到大排列为:"+num2+"<"+num1+"<"+num3);
                }else{
                    System.out.println("数字从小到大排列为:"+num1+"<"+num2+"<"+num3);
                }
            }
            break;
        case 6:            
            break;
        default:
            break;
        }
        
    }

}

import java.util.ArrayList;
import java.util.Scanner;
import java.util.Collections;

class App {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        ArrayList<Double> numbers = new ArrayList<Double>();
        boolean done = false;
        while (!done) {
            printMenu();
            switch (scanner.nextInt()) {
                case 0:
                    System.out.print("Input a new number: ");
                    numbers.add(scanner.nextDouble());
                    break;
                case 1:
                    System.out.print("Max: ");
                    System.out.println(Collections.max(numbers));
                    break;
                case 2:
                    System.out.print("Sum: ");
                    System.out.println(numbers.stream().mapToDouble(f -> f).sum());
                    break;
                case 3:
                    System.out.print("Range: ");
                    System.out.println(Collections.max(numbers) - Collections.min(numbers));
                    break;
                case 4:
                    System.out.print("Average: ");
                    System.out.println(numbers.stream().mapToDouble(f -> f).sum() / numbers.size());
                    break;
                case 5:
                    Collections.sort(numbers);
                    for (int i = 0; i < numbers.size(); i++)
                        System.out.print(numbers.get(i) + " ");
                    System.out.print("\n");
                    break;
                case 6:
                    done = true;
                    break;
            }
        }
        scanner.close();
    }

    static void printMenu() {
        System.out.println("(0) Input a new number");
        System.out.println("(1) Find the maximum number");
        System.out.println("(2) Calculate the sum");
        System.out.println("(3) Calculate the range");
        System.out.println("(4) Calculate the average");
        System.out.println("(5) Print sorted numbers");
        System.out.println("(6) Exit");
        System.out.print("Input your choice: ");;
    }
}