4.24作业

作业1:完善menu注册功能,抽奖,看小故事等功能

package a;

import java.util.*;

public class menu {
public static void main(String[] args) {
mainMenu();
}

public static void mainMenu() {
Scanner input = new Scanner(System.in);
System.out.println("1.登录");
System.out.println("2.注册");
System.out.println("3.幸运抽奖.");
System.out.println("4.看小故事,");
System.out.println("5.退出系统");
System.out.println("请选择");
int i = input.nextInt();
switch (i) {
case 1:
login();
break;
case 2:
zhuce();
break;
case 3:
choujiang();
break;
case 4:
story();
break;
case 5:
tuichu();
break;

}
}

public static void login() {
// TODO Auto-generated method stub
Scanner input = new Scanner(System.in);
System.out.println("输入用户名");
String uname = input.next();
System.out.println("输入密码");
String upwd = input.next();
if (uname.equals("zs") && upwd.equals("123")) {
System.out.println("登录成功");
} else {
System.out.println("登录失败");
}
returnMain();

}

public static void zhuce() {
Scanner input = new Scanner(System.in);
System.out.println("用户名");
String uname = input.next();
System.out.println("密码");
String upwd = input.next();
if (uname.equals(null) || upwd.equals(null)) {
System.out.println("注册失败");
} else {
System.out.println("注册成功");
}
returnMain();
}

private static void choujiang() {
Scanner input = new Scanner(System.in);
System.out.println("请输入四位会员卡号：");
int x = input.nextInt();
Random r = new Random();
int j = r.nextInt(10);
if (x / 100 * 10 == j) {
System.out.println("恭喜 你中奖了!");
} else {
System.out.println("感谢您的参与");
}
returnMain();
}

public static void story() {
Scanner input = new Scanner(System.in);
System.out.println("请选择你想看的故事：");
System.out.println("1.从前有座山");
System.out.println("2.从前有另一座山");
int a = input.nextInt();
switch (a) {
case 1:
System.out.println("从前有座山，山里有个庙，庙里有个小和尚和老和尚，老和尚给小和尚讲从前有座山……");
break;
case 2:
System.out.println("从前有座山，然后炸了，全剧终");
break;
}
returnMain();
}

public static void tuichu() {
System.out.println("是否退出系统Y/N");
Scanner input = new Scanner(System.in);
String a = input.next();
if (a.equalsIgnoreCase("y")) {
System.out.println("退出系统成功");
} else {
returnMain();
}
}

public static void returnMain() {
System.out.println("是否返回主菜单?Y/N");
Scanner input = new Scanner(System.in);
if (input.next().equalsIgnoreCase("Y")) {
mainMenu();
} else {
System.out.println("谢谢使用");
}
}
}

2.编写一个方法，求整数n的阶乘，例如5的阶乘是1*2*3*4*5。 [必做题]

package a;

import java.util.*;

public class jiecheng {
public static int jc(int n) {
int cj=1;
for (int i = 1; i <= n; i++) {
cj*=i;
}
return cj;
}
public static void main(String[] args) {
Scanner sc= new Scanner(System.in);
System.out.println("请输入要求阶乘的数字：");
int i=sc.nextInt();
System.out.println("该数字的阶乘为：" + jc(i));
}
}

3.编写一个方法，判断该年份是平年还是闰年。

package a;

import java.util.*;

public class year {
public static void year(int n) {
if (n % 4 == 0 && n % 100 != 0 || n % 400 == 0) {
System.out.println("该年是闰年");
} else {
System.out.println("该年是平年");
}
}

public static void main(String[] args) {
year a = new year();
Scanner sc = new Scanner(System.in);
System.out.println("请输入年份：");
int i=sc.nextInt();
year(i);
}
}