Java第四次作业
上机练习:
1.输入一个年份,判断是不是闰年(能被4整除但不能被100整除,或者能被400整除)
1 package test; 2 3 import java.util.Scanner; 4 5 public class Lwk { 6 7 public static void main(String[] args) { 8 // TODO Auto-generated method stub 9 Scanner input = new Scanner(System.in); 10 System.out.println("请输入年份"); 11 int year = input.nextInt(); 12 if (year % 4 == 0 && year % 100 != 0 || year % 400 == 0) { 13 System.out.println("是闰年"); 14 } 15 else { 16 System.out.println("不是闰年"); 17 } 18 } 19 20 }
2.输入一个4位会员卡号,如果百位数字是随机数,就输出是幸运会员,否则就输出不是.
1 package test; 2 3 import java.util.Random; 4 import java.util.Scanner; 5 6 public class Lwk0 { 7 8 public static void main(String[] args) { 9 // TODO Auto-generated method stub 10 Scanner input = new Scanner(System.in); 11 System.out.println("请输入一个四位数"); 12 int a = input.nextInt(); 13 Random r = new Random(); 14 int b = r.nextInt(10); 15 if (b == a / 100 % 10) { 16 System.out.println("是幸运会员"); 17 } 18 else { 19 System.out.println("不是幸运会员"); 20 } 21 } 22 23 }
3.已知函数,输入x的值,输出对应的y的值.
x + 3 ( x > 0 )
y = 0 ( x = 0 )
x*2 –1 ( x < 0 )
1 package test; 2 3 import java.util.Scanner; 4 5 public class Lwk1 { 6 7 public static void main(String[] args) { 8 // TODO Auto-generated method stub 9 Scanner input = new Scanner(System.in); 10 System.out.println("请输入x的值"); 11 int x = input.nextInt(); 12 int y = 0; 13 if (x > 0) { 14 y = x + 3; 15 } 16 else if (x < 0) { 17 y = x * 2 - 1; 18 } 19 else { 20 y = 0; 21 } 22 System.out.println("y=" + y); 23 } 24 25 }
4.输入三个数,判断能否构成三角形(任意两边之和大于第三边)
1 package test; 2 3 import java.util.Scanner; 4 5 public class Lwk2 { 6 7 public static void main(String[] args) { 8 // TODO Auto-generated method stub 9 Scanner input = new Scanner(System.in); 10 System.out.println("请输入三个数"); 11 int a = input.nextInt(); 12 int b = input.nextInt(); 13 int c = input.nextInt(); 14 if (a + b > c && a + c > b && b + c > a) { 15 System.out.println("a、b、c可以组成三角形"); 16 } 17 else { 18 System.out.println("a、b、c不能组成三角形"); 19 } 20 21 } 22 23 }
作业:
1 输入年份月份,输出该月的天数(闰年2月29天,条件参考上机练习1)
1 package test; 2 3 import java.util.Scanner; 4 5 public class Lwk3 { 6 7 public static void main(String[] args) { 8 // TODO Auto-generated method stub 9 Scanner input = new Scanner(System.in); 10 System.out.println("请输入年份"); 11 int year = input.nextInt(); 12 System.out.println("请输入月份"); 13 int month = input.nextInt(); 14 switch (month) { 15 case 4: 16 case 6: 17 case 9: 18 case 11: 19 System.out.println("该月份有30天"); 20 break; 21 case 2: 22 if (year % 4 == 0 && year % 100 != 0 || year % 400 == 0) { 23 System.out.println("该月份有29天"); 24 } 25 else { 26 System.out.println("该月份有28天"); 27 } 28 break; 29 default: 30 System.out.println("该月份有31天"); 31 break; 32 } 33 34 } 35 36 }
2、给定一个成绩a,使用switch结构求出a的等级
。A:90-100,B:80-89,C:70-79,D:60-69,E:0~59
1 package test; 2 3 import java.util.Scanner; 4 5 public class Lwk4 { 6 7 public static void main(String[] args) { 8 // TODO Auto-generated method stub 9 Scanner input = new Scanner(System.in); 10 System.out.println("请输入成绩"); 11 int a = input.nextInt(); 12 switch (a/10) { 13 case 10: 14 case 9: 15 System.out.println("A"); 16 break; 17 case 8: 18 System.out.println("B"); 19 break; 20 case 7: 21 System.out.println("C"); 22 break; 23 case 6: 24 System.out.println("D"); 25 break; 26 default: 27 System.out.println("E"); 28 break; 29 } 30 31 } 32 33 }
3、输入一个数字,判断是一个奇数还是偶数
1 package test; 2 3 import java.util.Scanner; 4 5 public class Lwk5 { 6 7 public static void main(String[] args) { 8 // TODO Auto-generated method stub 9 Scanner input = new Scanner(System.in); 10 System.out.println("请输入一个数"); 11 int a = input.nextInt(); 12 if (a % 2 == 0 && a != 0) { 13 System.out.println("该数为偶数"); 14 } 15 else if (a == 0) { 16 System.out.println("该数非奇非偶"); 17 } 18 else { 19 System.out.println("该数为偶数"); 20 } 21 } 22 23 }
4、编写程序, 判断一个变量x的值,如果是1, 输出x=1,如果是5,输出x=5,如果是 10,输出 x=10,除了以上几个值,都输出x=none。
1 package test; 2 3 import java.util.Scanner; 4 5 public class Lwk6 { 6 7 public static void main(String[] args) { 8 // TODO Auto-generated method stub 9 Scanner input = new Scanner(System.in); 10 System.out.println("请输入x的值"); 11 int x = input.nextInt(); 12 if (x == 1 || x == 5 || x == 10) { 13 System.out.println("x=" + x); 14 } 15 else { 16 System.out.println("x=none"); 17 } 18 19 } 20 21 }
5、判断一个数字是否能被5和6同时整除(打印能被5和6整除),或只能被5整除(打印能被5整除 ),或只能被6整除,(打印能被6整除),不能被5或6整除,(打印不能被5或6整除)
1 package test; 2 3 import java.util.Scanner; 4 5 public class Lwk7 { 6 7 public static void main(String[] args) { 8 // TODO Auto-generated method stub 9 Scanner input = new Scanner(System.in); 10 System.out.println("请输入一个数"); 11 int a = input.nextInt(); 12 if (a % 5 == 0 && a % 6 == 0) { 13 System.out.println("能被5和6整除"); 14 } 15 else if (a % 5 == 0 && a % 6 != 0) { 16 System.out.println("只能被5整除"); 17 } 18 else if (a % 5 != 0 && a % 6 == 0) { 19 System.out.println("只能被6整除"); 20 } 21 else { 22 System.out.println("不能被5或6整除"); 23 } 24 25 } 26 27 }