class Demo02 {    public static void main(String[] args)     {        System.out.println(add(1,2));        System.out.println(add(1,2,8));        System.out.println(add(1.1,2.2));    }    public static int add(int a,int b){           return a+b;    }    public static int add(int a,int b,int c){           return a+b+c;    }    public static double add(double a,double b){           return a+b;    }}

 

import java.util.Scanner;class Demo01{    public static void main(String[] args)     {        String[] pinpai = {
   "MacBookAir","ThinkpadT450","ASUS-FL5800"};        double[] size = {
   13.0,14.0,15.6};        double[] price ={
   6988.88,5999.99,4999.5};        int[] count = {
   5,10,18};        while(true){             switch (xz())             {             case 1:show(pinpai,size,price,count);                     break;             case 2:xg(pinpai,size,price,count);                     break;             case 3:                 return;             default:                 System.out.println("输入有误");                     break;                          }        }    }    public static int xz(){        System.out.println("1、查看商品库存");        System.out.println("2、修改库存数量");        System.out.println("3、退出");        System.out.println("输入操作编号");        System.out.println("-----------------------------");        Scanner sc = new Scanner(System.in);        int num = sc.nextInt();        return num;    }        public static void show (String[] pinpai,double[] size,double[] price,int[] count){        System.out.println("----------------------商城库存清单--------------------");        System.out.println("品牌型号\t尺寸\t价格\t库存数");        int csum = 0;        for(int i=0;i