1.编写一个方法,实现冒泡排序(由小到大),并调用该方法
public class lwm1 { // 编写一个方法,实现冒泡排序(由小到大),并调用该方法 public static void a(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; } } } } public static void main(String[] args) { int b[] = { 1, 22, 3, 44, 5, 66 }; a(b); for (int i = 0; i < b.length; i++) { System.out.println(b[i]); } } }
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]
public class lwm2 { // 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] 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(5)); } }
3.编写一个方法,判断该年份是平年还是闰年。[必做题]
import java.util.Scanner; public class lwm3 { // 3.编写一个方法,判断该年份是平年还是闰年。[必做题] public static void a(int a) { if (a % 4 == 0 && a % 100 != 0 || a % 400 == 0) { System.out.println("闰年"); } else { System.out.println("平年"); } } public static void main(String[] args) { Scanner input = new Scanner(System.in); System.out.println("输入年份"); a(input.nextInt()); } }
4.课堂没完成的menu菜单,实现幸运抽奖功能
import java.util.Random; import java.util.Scanner; public class lwm4 { // 4.课堂没完成的menu菜单,实现幸运抽奖功能 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"); System.out.println("请选择"); int i=input.nextInt(); switch(i){ case(1): login(); break; case(2): reg(); break; case(3): luckly(); break; } } public static void returnMenu(){ Scanner input=new Scanner(System.in); System.out.println("是否返回主菜单"); if (input.next().equalsIgnoreCase("Y")) { mainMenu(); }else{ System.out.println("谢谢使用"); } } private 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 upwd=input.next(); if (uname.equals("zs")&&upwd.equals("1234")) { System.out.println("ok"); }else{ System.out.println("fail"); } returnMenu(); } private static void reg(){ 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("再次输入密码"); String uppwd=input.next(); if(upwd.equals(input())==uppwd.equals(input())){ System.out.println("注册成功"); System.out.println("用户名"+uname+"密码"+upwd); }else{ System.out.println("密码错误"); } returnMenu(); } private static Object input() { // TODO Auto-generated method stub return null; } private static void luckly(){ Scanner input=new Scanner(System.in); Random r=new Random(); int luck=r.nextInt(10); System.out.println("输入四位数会员卡号"); int id=input.nextInt(); if (luck==id) { System.out.println("幸运会员"); }else{ System.out.println("不是幸运会员"); } returnMenu(); } public static void main(String[] args) { mainMenu(); } }