java第三次作业

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 one;
import java.util.Scanner;

public class one1 {
    public static void main(String[] args) {
        int year;
        Scanner sc= new Scanner(System.in);
        System.out.println("year=");
        year=sc.nextInt();
        if((year%4==0&&year%100!=0)||(year%400==0)){
            System.out.println(year+"是闰年");
    }else{
        System.out.println(year+"是平年");
    }
}
}

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 one;
import java.util.Scanner;

public class one1 {
    public static void main(String[] args) {
        Scanner input = new Scanner(System.in);
        System.out.println("请输入一个四位数的会员卡号:");
        int vipcard=input.nextInt();
        if(vipcard<1000||vipcard>9999){
            System.out.println("输入错误");
        }else {
            int bai=0;
            bai=vipcard/100%10;
            if(bai%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 one;
import java.util.Scanner;

public class one1 {
    public static void main(String[] args) {
        Scanner input = new Scanner(System.in);
        System.out.println("请输入x值: ");
        int x=input.nextInt();
        int y=0;
        if(x>0){
            y=x+3;
            System.out.println("y="+y);
        }else if(x<0) {
            y=x*2-1;
            System.out.println("y="+y);
        }else {
            y=0;
            System.out.println("y="+0);
        }
    }
}

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 one;
import java.util.Scanner;

public class one1 {
    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<=0||b<=0||c<=0) {
            System.out.println("请重新输入!");
        }else {
            if(a+b>c&&a+c>b&&b+c>a) {
                System.out.println("您输入的值可以组成三角形! ");
            }else {
                System.out.println("您输入的值不可以组成三角形! ");
            }
        }
    }
}