Java第十次作业
1编写一个方法,实现冒泡排序法(由小到大),并调用该方法
import java.util.Scanner; public class txt2 { public static void txt2() { Scanner input = new Scanner(System.in); System.out.println("请输入数组"); int []a=new int [5]; for(int i=0;i<a.length;i++){ a[i]=input.nextInt(); } 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; } } } for(int i:a){ System.out.println(i); } } public static void main(String[] args){ txt2(); } }
2编写一个方法,求n的阶乘;
public class work6 { public static int jc(int n){ int sum=1; for(int i=1;i<=n;i++){ sum=sum*i; } return sum; } public static void main(String[] args){ System.out.println(jc(6)); } }
3 编写一个方法,判断该年份是平年还是闰年。
public class work6 { public static int pr(int n){ if(n%4==0&&n%100!=0||n%400==0) System.out.println("是闰年"); else System.out.println("是平年"); return n; } public static void main(String[] args){ System.out.println(pr(2020)); } }
4 课堂没有完成的menu菜单,实现幸运抽奖功能
import java.util.Random; import java.util.Scanner; public class work7 { public static void mainMenu() { 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.退出系统"); System.out.println("请选择:"); int i = input.nextInt(); switch (i) { case 1: login(); break; case 2: register(); break; case 3: xycj(); break; } } public static void register() { 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 pwd = input.next(); System.out.println("注册成功"); returnMain(); } public static void returnMain() { Scanner input = new Scanner(System.in); System.out.println("是否返回主菜单?Y/N"); if (input.next().equalsIgnoreCase("Y")) mainMenu(); else System.out.println("谢谢使用"); } public static void login() { 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 pwd = input.next(); if (uname.equals("admin") && pwd.equals("admin")) System.out.println("成功"); else System.out.println("失败"); returnMain(); } public static void xycj() { Scanner input = new Scanner(System.in); System.out.println("输入一个4位会员卡号"); int number = input.nextInt(); int bw = number / 100 % 10; Random r = new Random(); int a = (int) r.nextInt(10); if (bw == a) { System.out.println("该用户是幸运会员"); } else { System.out.println("该用户不是幸运会员"); } returnMain(); } public static void main(String[] args) { mainMenu(); } }