Java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
import java.util.Scanner; public class zxcz { public static void px() { Scanner input = new Scanner(System.in); System.out.println("输入5个数:"); int a[] = new int[5]; int b; for (int i = 0; i < a.length; i++) { a[i] = input.nextInt(); } for (int i = 0; i < a.length - 1; i++) { for (int j = i+1; j < a.length; j++) { if (a[i] > a[j]) { b = a[i]; a[i] = a[j]; a[j] = b; } } } for (int i = 0; i < a.length; i++) { System.out.print(a[i]); System.out.print(" "); } System.out.println(); } public static void main(String[] args) { px(); } }
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]
import java.util.Scanner; public class zxcz { public static int jc(int a){ int sum=1; for(int i=1;i<=a;i++){ 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 zxcz { public static void pr() { Scanner input=new Scanner(System.in); int a=input.nextInt(); if (a % 400 == 0 & a % 100 != 0 | a % 4 == 0) System.out.println("该年为闰年"); else System.out.println("该年为平年"); } public static void main(String[] args) { pr(); } }
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 zxcz { 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: draw(); 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("1")&&pwd.equals("1")) System.out.println("成功"); else System.out.println("失败"); returnMain(); } public static void draw(){ Scanner input = new Scanner(System.in); Random r=new Random(); int a=r.nextInt(10); System.out.println("输入四位会员卡号"); int kahao=input.nextInt(); int c=kahao%100/10; System.out.println("幸运数字为"+a); if(c==a){ System.out.println("是幸运会员"); } else{ System.out.println("不是幸运会员"); } returnMain(); } public static void main(String[] args) { mainMenu(); } }