java方法的使用作业-0512

import java.util.Scanner;
import java.util.Random;
class zuoye 
{
    public static void main(String[] args) 
    {
        String[] arr = {"董斌","张锐","王荣臣","韩凯","张禄","刘继勋","张维","牛攀"};
        //遍历名字
        //bl(arr);
        //随机点名
        //sj(arr);
        //库存界面
        //jm();
        //整数相加
        //System.out.println(add(1,2));
        //小数相加
        //System.out.println(add(1.6,3.5));
        //整数判断相等
        //System.out.println(pd(1,2));
        //小数判断相等
        //System.out.println(pd(1.6,3.5));
        //m行 n列的星星矩形
        //jx(3,9);
        //nn乘法表
        //cfb(3);
        //长方形求面积
        //System.out.println(cfx(5.6,5));
        //圆形求面积
        //System.out.println(yx(8));
        //打印除9以外100内的数字 一行5个
        //dys();
        //打印100内的素数 一行5个 记录个数
        //zs();

    }
    public static void bl(String[] arr){
        for(int i = 0;i<arr.length;i++){
             System.out.println(arr[i]);
        }
    }
    public static void sj(String[] arr){
        Random r = new Random();
        int i = r.nextInt(8);
        System.out.println(arr[i]);

    }
    public static void jm(){
        System.out.println("------------------------库存管理------------------------");
        System.out.println("1.查看库存清单");
        System.out.println("2.修改商品库存数量");
        System.out.println("3.退出");
        System.out.println("请输入要执行的操作编号：");
        Scanner sc = new Scanner(System.in);
        int num = sc.nextInt();

        switch (num)
        {
        case 1:
             kc();
        break;
        case 2:
             xg();
        break;
        case 3:
            tc();
        break;
        }
    }
    public static void kc(){
        System.out.println("---------------------------"+"商城库存清单"+"-------------------------------");
        System.out.println("品牌型号"+"	"+"尺寸"+"	"+"价格"+"	"+"库存数");
        String  Product_name1 = "MacBookAir";
        String  Product_name2 = "ThinkpadT450";
        String  Product_name3 = "ASUS-FL5800";
        double  size1 = 13.3;
        double  size2 = 14.0;
        double  size3 = 15.6;
        double  price1 = 6988.88;
        double  price2 = 5999.99;
        double  price3 = 4999.5;
        int  num1 = 5;
        int  num2 = 10;
        int  num3 = 18;
        System.out.println(Product_name1+"	"+size1+"	"+price1+"	"+num1);
        System.out.println(Product_name2+"	"+size2+"	"+price2+"	"+num2);
        System.out.println(Product_name3+"	"+size3+"	"+price3+"	"+num3);
        System.out.println("------------------------------------------------------------------------");
        int anum = num1 + num2 + num3;
        double aprice = price1 + price2 + price3;
        System.out.println("总库存数："+anum);
        System.out.println("库存商品总金额："+aprice);
    }
    public static void xg(){
        System.out.println("请输入需要修改的商品编号");
        Scanner sc = new Scanner(System.in);
        int bh = sc.nextInt();
        System.out.println("请输入更改数量");
        int xsl = sc.nextInt();
        int num1 =5;
        int num2 =10;
        int num3 =18;
        if(bh==1){
              num1 = xsl;
        }else if(bh==2){
              num2 = xsl;
        }else if(bh==3){
              num3 = xsl;
        }else{
              System.out.println("输入有误");
        }
        System.out.println("---------------------------"+"商城库存清单"+"-------------------------------");
        System.out.println("品牌型号"+"	"+"尺寸"+"	"+"价格"+"	"+"库存数");
        String  Product_name1 = "MacBookAir";
        String  Product_name2 = "ThinkpadT450";
        String  Product_name3 = "ASUS-FL5800";
        double  size1 = 13.3;
        double  size2 = 14.0;
        double  size3 = 15.6;
        double  price1 = 6988.88;
        double  price2 = 5999.99;
        double  price3 = 4999.5;
        System.out.println(Product_name1+"	"+size1+"	"+price1+"	"+num1);
        System.out.println(Product_name2+"	"+size2+"	"+price2+"	"+num2);
        System.out.println(Product_name3+"	"+size3+"	"+price3+"	"+num3);
        System.out.println("------------------------------------------------------------------------");
        int anum = num1 + num2 + num3;
        double aprice = price1 + price2 + price3;
        System.out.println("总库存数："+anum);
        System.out.println("库存商品总金额："+aprice);
    }
    public static void tc(){
        return;
    }
    public static int add(int a,int b){
        
         return a + b;
    }
    public static double add(double a,double b){
        
         return a + b;
    }
    public static boolean pd(int a,int b){
         return a==b?true:false;
    }
    public static boolean pd(double a,double b){
         return a==b?true:false;
    }
    public static void jx(int m,int n){
         for(int i = 0;i<m;i++){
            for(int j = 0;j<n;j++){
               System.out.print("*");
            }
            System.out.println();
         }
    }
    public static void cfb(int n){
          for(int i =1;i<=n;i++){
             for(int j = 1;j<=i;j++){
                 System.out.print(j+"*"+i+"="+i*j+"	");
             }
             System.out.println();
          }
    }
    public static double cfx(double a,double b){
             return a*b;
    }
    public static double yx(double r){
             return r*r*Math.PI;
    }
    public static void dys(){
             int j = 0;
             for(int i = 1;i<=100;i++){    
             if(i==9){
               continue;
             }else if(i%10==9){
             continue;
             }else if(i/10>=9 && i/10<10){
             continue;
             }else{
                 j++;
                 if(j<6){
                    System.out.print(i+"	");
                 }else{
                     j = 1;
                    System.out.print("
"+i+"	");
                    
                 }
             }
            
        }
    }
    public static void zs(){
        int k = 0;
        int n = 0;
        for(int i = 2;i <=100;i++){
            int zhishu = 1; //1表示是质数
            for (int j =2;j< i ;j++){
                if(i%j == 0){
                    zhishu = 0;  //0表示不是质数
                }
            }
            if(zhishu == 1){
                k++;
                n++;
                if(k<6){
                     System.out.print(i+"	");
                }else{
                     k=1;
                    System.out.print("
"+i+"	");
                }
                    
            }
            
        }
        System.out.println();
        System.out.println(n);
    }

}