# 第十周java作业

1.编写一个方法，实现冒泡排序（由小到大），并调用该方法

package work10;

public class test1 {

/**
* @param args
*/
public static void main(String[] args) {
// TODO Auto-generated method stub
int []x={1,3,2,5,8,7,9};
mp(x);
for (int i = 0; i < x.length; i++) {
System.out.println(x[i]);
}
}
public static void mp(int[]a){
for (int i = 0; i < a.length - 1; i++) {
for (int j = 0; j < a.length - 1 - i; j++) {
if (a[j] > a[j + 1]) {
int temp = a[j];
a[j] = a[j + 1];
a[j + 1] = temp;
}
}
}
}
}

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 work10;

public class Test2 {

/**
* @param args
*/
public static void main(String[] args) {
// TODO Auto-generated method stub
int sum=jc(5);
System.out.println(sum);
}
public static int jc(int n){
int sum=1;
for (int i =1; i <=n; i++) {
sum*=i;
}
return sum;
}

}

3.编写一个方法，判断该年份是平年还是闰年。[必做题]

package work10;

import java.util.Scanner;

public class Test3 {

/**
* @param args
*/
public static void main(String[] args) {
// TODO Auto-generated method stub
year();
}
public static void year(){
Scanner input=new Scanner(System.in);
System.out.println("输入年份");
int year=input.nextInt();
if(year%4==0&&year%100!=0||year%400==0){
System.out.println(year+"是闰年");
}else{
System.out.println(year+"是平年");
}
}
}

package work10;

import java.util.Random;
import java.util.Scanner;

public class Test4 {

/**
* @param args
*/
public static void main(String[] args) {
}
Scanner input = new Scanner(System.in);
System.out.println("欢迎使用本系统");
System.out.println("1.登录");
System.out.println("2.注册");
System.out.println("3.幸运抽奖");
System.out.println("4.退出");
System.out.println("请选择");
int i = input.nextInt();
switch (i) {
case 1:
break;
case 2:
reg();
break;
case 3:
lucky();

}

}

public static void lucky() {
// 输入四位会员卡号，如果百位数等于随机数，幸运会员。否则不是。同时也要询问是否返回主菜单
Scanner input = new Scanner(System.in);
System.out.println("输入一个四位数");
Random r = new Random();
int x = r.nextInt(10);
int num = input.nextInt();
while (num < 1000 || num > 10000) {
System.out.println("输入有误,重新输入");
num = input.nextInt();
if (num >= 1000 && num < 10000) {
break;
}
}
int bai = num % 1000 / 100;
if (bai == x) {
System.out.println("幸运会员");
} else {
System.out.println("不是幸运会员");
}

returnMain();
}

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

public static void reg() {
// TODO Auto-generated method stub
Scanner input = new Scanner(System.in);
System.out.println("输入要注册的用户名");
String uname = input.next();
System.out.println("输入注册密码");
String upwd = input.next();
System.out.println("注册成功");
returnMain();

}

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("ls") && upwd.equals("123")) {
System.out.println("ok");
} else {
System.out.println("fail");
}
returnMain();
}
}

posted @ 2021-05-09 14:55  星星邮寄者  阅读(48)  评论(0编辑  收藏  举报