第三周作业

1.

package sdsv;
import java.util.Scanner;
public class demo {

    public static void main(String[] args) {
         @SuppressWarnings("resource")
            Scanner sc=new Scanner(System.in);
            int a=sc.nextInt();
            if(a%4==0||a%400==0) {
                System.out.println("此年为闰年");
            }else {
                System.out.println("此年不是闰年");
            }
        }    
}

2.package sdsv;
import java.util.Scanner;
public class demo {

    public static void main(String[] args) {
        Scanner input=new Scanner(System.in);
        System.out.println("请输入四位会员卡号");
        int a=input.nextInt();
        switch(a%1000/100) {
        case 3:
        case 6:
        case 9:
            System.out.println("幸运会员");break;
        default:
            System.out.println("不是幸运会员");break;
        }
    }

}

3.

package sdsv;
import java.util.Scanner;
public class demo {

    public static void main(String[] args) {
        Scanner input=new Scanner(System.in);
        System.out.println("请输入x的值");
        int x=input.nextInt();
        int y;
        if(x>0)
            y=x+3;
        else if(x==0)
            y=0;
        else
            y=x*x-1;
        System.out.println("y的值是"+y);
    }

}

4.

package sdsv;
import java.util.Scanner;
public class demo {

    public static void main(String[] args) {
         Scanner input=new Scanner(System.in);
            System.out.println("请输入三个数");
            int a=input.nextInt();
            int b=input.nextInt();
            int c=input.nextInt();
            if(a+b>c&&a+c>b&&b+c>a)
               System.out.println("能够成三角形");
            else
                System.out.println("不能构成三角形");
        }

    }