第十周作业
1.编写一个方法,实现冒泡排序(由小到大),并调用该方法
package task; import java.util.Scanner; public class T1 { public static void px(int []a) { for (int i = 0; i < a.length; i++) { for (int j = 0; j < a.length; j++) { if(a[i]<a[j]) { int t; t=a[i]; a[i]=a[j]; a[j]=t; } } } } public static void main(String[] args) { Scanner input=new Scanner(System.in); int a[]=new int[6]; for (int i = 0; i < a.length; i++) { a[i]=input.nextInt(); } px(a); for (int i = 0; i < a.length; i++) { System.out.println(a[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]
package task; import java.util.Scanner; public class T1 { public static int jc(int a) { int sum=0; for (int i = 1; i <= a; i++) { sum+=(i*i); } return sum; } public static void main(String[] args) { Scanner input=new Scanner(System.in); int n=input.nextInt(); System.out.print(jc(n)); } }
3.编写一个方法,判断该年份是平年还是闰年。[必做题]
package task; import java.util.Scanner; public class T1 { public static void nf(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); nf(input.nextInt()); } }
4.课堂没完成的menu菜单,实现幸运抽奖功能
package task; import java.util.Random; import java.util.Scanner; public class T1 { public static void main(String[] args) { mainMenu(); } 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: zhuce(); break; case 3: xingyuncj(); break; case 4: 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(); } public static void xingyuncj() { Scanner input = new Scanner(System.in); System.out.println("幸运抽奖"); System.out.println("输入会员号"); int a=input.nextInt(); Random i=new Random(); int b=i.nextInt(10); if(a==b) { System.out.println("恭喜中奖"); } else { System.out.println("未中奖"); } 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"); } } }