第三次java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)

package wjb;
import java.util.Scanner;
public class wjbc {

    public static void main(String[] args) {
        System.out.println("请输入年份");
        Scanner input=new Scanner(System.in);
        int a=input.nextInt();
        if(a%4==0||a%100!=0&&a%400==0){
            System.out.println("是");
        }else{
            System.out.println("不是");
        }
    }
}

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.

package wjb;
import java.util.Scanner;
public class wjbc {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        System.out.println("请输入四位会员卡号");
        Scanner input=new Scanner(System.in);
        int a=input.nextInt();
        int b;
        b=a/100%10;
        if(b%3==0){
            System.out.println("是幸运会员");
        }else{
            System.out.println("不是幸运会员");
        }
    }
}

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 )

package wjb;
import java.util.Scanner;
public class wjbc {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        System.out.println("请输入x");
        Scanner input=new Scanner(System.in);
        int x=input.nextInt();
        int y;
        if(x>0){
            y=x+3;
            System.out.println(y);
        }else if(x==0){
            y=0;
            System.out.println(y);
        }else if(x<0){
            y=x*2-1;
            System.out.println(y);
        }
    }
}

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)

package wjb;
import java.util.Scanner;
public class wjbc {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        System.out.println("请输入三个数");
        Scanner input=new Scanner(System.in);
        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("能构成三角形");
        }else{
            System.out.println("不能构成三角形");
        }
    }
}