第十次作业
1、编写一个方法,实现冒泡排序(由小到大),并调用该方法
package mrb; public class Asd { /** * @param args */ public static void main(String[] args) { // TODO Auto-generated method stub int []a={100,88,79,98}; mp(a); for (int i = 0; i < a.length; i++) { System.out.println(a[i]); } } public static void mp(int[]b){ for (int i = 0; i < b.length - 1; i++) { for (int j = 0; j < b.length - 1 - i; j++) { if (b[j] > b[j + 1]) { int temp = b[j]; b[j] = b[j + 1]; b[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 mrb; public class Asd { /** * @param args */ public static void main(String[] args) { // TODO Auto-generated method stub int sum=jc(6); System.out.println(sum); } public static int jc(int a){ int sum=1; for (int i =1; i <=a; 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 mrb; import java.util.Scanner; public class Asd { /** * @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("请输入年份"); int year=input.nextInt(); if(year%4==0&&year%10!=0||year%400==0){ System.out.println("是闰年"); }else{ System.out.println("是平年"); } } }
4.课堂没完成的menu菜单,实现幸运抽奖功能
package mrb; import java.util.Random; import java.util.Scanner; public class Asd { /** * @param args */ public static void main(String[] args) { // TODO Auto-generated method stub 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"); System.out.println("请选择"); int i=input.nextInt(); switch(i){ case 1: login(); break; case 2: reg(); break; case 3: lucky(); } } private 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("请输入四位会员卡号"); Random r=new Random(); int x=r.nextInt(100); int a=input.nextInt(); while(a<1000||a>10000){ System.out.println("请重新输入"); a=input.nextInt(); if(a<1000||a>10000){ break; } } int bw=a%1000/100; if(bw==x){ System.out.println("恭喜成为幸运会员"); }else{ System.out.println("很遗憾不是幸运会员"); } 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")) mainMenu(); 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(); } 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 upwd=input.next(); if(uname.equals("zs")&&upwd.equals("123")){ System.out.println("ok"); }else{ System.out.println("fail"); } returnMain(); } }