第三周作业

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 text;
 2 import java.util.Scanner;
 3 
 4 public class note1 {
 5     public static void main(String[] args) {
 6         Scanner input = new Scanner(System.in);
 7          System.out.println("输入一个年份");
 8            int year = input.nextInt();
 9            if ((year % 4 == 0 && year % 100 != 0) || year % 400 == 0) {
10                System.out.println(year + "是闰年");
11            } else {
12                System.out.println(year + "不是闰年");
13            }
14 
15     }
16 
17 }

2.输入一个4位会员卡号,如果百位数字是3的倍数,就输出是幸运会员,否则就输出不是.

 1 package text;
 2 import java.util.Scanner;
 3 
 4 public class note1 {
 5     public static void main(String[] args) {
 6         Scanner input = new Scanner(System.in);
 7         System.out.println("输入一个4位会员卡号:");
 8         int card = input.nextInt();
 9         int bai = card / 100 % 10;
10         if(card > 9999 || card < 1000){
11             System.out.println("会员卡号错误");
12         }else if(bai % 3 == 0){
13             System.out.println(card + "是幸运会员");
14         }else{
15             System.out.println("不是幸运会员");
16         }
17 
18     }
19 
20 }

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 )
x2 –1 ( x < 0 )

 1 package text;
 2 import java.util.Scanner;
 3 
 4 public class note1 {
 5     public static void main(String[] args) {
 6         Scanner input = new Scanner(System.in);
 7          System.out.println("输入一个x值:");
 8           double x = input.nextDouble();
 9            if (x > 0) {
10                System.out.println("y =" + (x + 3));
11            } else if(x == 0){
12                System.out.println("y =" + x);
13            }else{
14                System.out.println("y =" + (x * 2 - 1));
15            }
16 
17     }
18 }

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 text;
 2 import java.util.Scanner;
 3 
 4 public class note1 {
 5     public static void main(String[] args) {
 6         Scanner input = new Scanner(System.in);
 7          System.out.println("输入三角形三条边:");
 8           int a = input.nextInt();
 9           int b = input.nextInt();
10           int c = input.nextInt();
11            if ((a+b)>c&&(a+c)>b&&(b+c)>a) {
12                System.out.println("可以构成三角形");
13            }else{
14                System.out.println("不可以构成三角形");
15            }
16 
17     }
18 
19 }