第一本十五章買家電

<pre class="java" name="code">package com.lljk;

import java.util.Scanner;

public class show {
	public void er() {
		show a = new show();

		double qian;
		Scanner input = new Scanner(System.in);
		String[] goods = new String[] { "電風扇", "洗衣機", "電視機", "冰箱", "空調機" };
		double[] price = new double[] { 124.23, 4500, 8800.90, 5000.88, 4456,
				12000.46 };

		System.out.println("編號\t商品\t價格\t");
		int[] shuzi = new int[] { 1, 2, 3, 4, 5 };
		for (int i = 0; i < shuzi.length; i++) {
			System.out.println(shuzi[i + 1] + "\n");
			System.out.println(goods[i] + "\n");
			System.out.println(a.pp(price[i]) + "\n");
		}
		System.out.println("請輸入你批發的商品編號");
		int u = input.nextInt();
		System.out.println("請輸入批發數量");
		int shu = input.nextInt();
		switch (u) {
		case 1:
			qian = shu * 123.23;
			break;
		case 2:
			qian = shu * 4500;
			break;
		case 3:
			qian = shu * 8800.9;
			break;
		case 4:
			qian = shu * 5000.88;
			break;
		case 5:
			qian = shu * 4456;
			break;
		}

	}

	public StringBuffer pp(double qian) {
		StringBuffer str = new StringBuffer(String.valueOf(qian));
		for (int f = str.indexOf(".") - 3; f > 0; f = f - 3) {
			str.insert(f, ",");
		}
		return str;
	}
}

package com.lljk;import java.util.Scanner;public class login {public void yi() {Scanner input=new Scanner(System.in);String zhanghao;int mi;System.out.println("請輸入用戶名");zhanghao = input.next();System.out.println("請輸入密碼");mi = input.nextInt();if ("tom".equals(zhanghao) && mi == 123456) {System.out.println("登陸成功");}else{System.out.println("denglu失敗");}}}