java第四次作业

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 School.Day4;
import java.util.Scanner;
public class Test01 {
    public static void main(String[] args){
        System.out.print("输入年份: ");
        Scanner s = new Scanner(System.in);
        int year = s.nextInt();
        if(year%100==0){
            if(year%400 ==0){
                System.out.println("该年是闰年");
            }else{
                System.out.println("该年是平年");
            }
        }else{
            if(year%4==0||year%400==0){
                System.out.println("该年是闰年");
            }else{
                System.out.println("该年是平年");
            }
        }
    }
}

  

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.

package School.Day4;
import java.util.Random;
import java.util.Scanner;
public class Test02 {
    public static void main(String[] args){
        Random r = new Random();
        Scanner s = new Scanner(System.in);
        System.out.print("输入会员号: ");
        int huiyuan = s.nextInt();
        int x = r.nextInt(9);
        System.out.println("幸运随机数: " + x);
        if(huiyuan%1000/100==x){
            System.out.println("恭喜您,中奖了!");
        }else{
            System.out.println("很遗憾,没中奖!");
        }
    }
}

  

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 )

package School.Day4;
import java.util.Scanner;
public class Test03 {
    public static void main(String[] args){
        System.out.print("输入X: ");
        Scanner s = new Scanner(System.in);
        int x = s.nextInt();
        int y;
        if(x>0){
            y = x+3;
        }else if(x==0){
            y = 0;
        }else {
            y = 2*x-1;
        }
        System.out.println("Y==" + 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 School.Day4;
import java.util.Scanner;
public class Test04 {
    public static void main(String[] args){
        Scanner s = new Scanner(System.in);
        System.out.print("输入边长: ");
        double a = s.nextDouble();
        System.out.print("输入边长: ");
        double b = s.nextDouble();
        System.out.print("输入边长: ");
        double c = s.nextDouble();
        if(a+b>c&&a+c>b&&b+c>a){
            System.out.println("可以构成三角形");
        }else{
            System.out.println("不可以构成三角形");
        }
    }
}

 

5. 输入年份月份,输出该月的天数

package School.Day4;
import java.util.Scanner;
public class Test05 {
    public static void main(String[] args){
        Scanner s = new Scanner(System.in);
        System.out.print("输入年份: ");
        int year = s.nextInt();
        System.out.print("输入月份: ");
        int month = s.nextInt();
        int day;
        switch(month){
            case 1:
            case 3:
            case 5:
            case 7:
            case 8:
            case 10:
            case 12:
                day = 31;
                break;
            case 2:
                day = 28;
                break;
            default:
                day = 30;
        }
        if(year%100==0){
            if(year%400==0&&month ==2){
                day = 29;
            }
        }else{
            if(year%4==0||year%400==0){
                if (month == 2) {
                    day = 29;
                }
            }
        }
        System.out.println( year + "年" + month + "月有" + day + "天" );
    }
}

  

  

6.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

package School.Day4;
import java.util.Scanner;
public class Test06 {
    public static void main(String[] args){
        Scanner s = new Scanner(System.in);
        System.out.print("输入成绩: ");
        int a = s.nextInt();
        switch(a/10){
            case 10:
            case 9:
                System.out.println("成绩等级:A");
                break;
            case 8:
                System.out.println("成绩等级:B");
                break;
            case 7:
                System.out.println("成绩等级:C");
                break;
            case 6:
                System.out.println("成绩等级:D");
                break;
            default:
                System.out.println("成绩等级:E");
        }
    }
}

  

7.输入一个数字,判断是一个奇数还是偶数 

package School.Day4;
import java.util.Scanner;
public class Test07 {
    public static void main(String[] args){
        System.out.print("输入数字: ");
        Scanner s = new Scanner(System.in);
        int x = s.nextInt();
        if(x%2==0){
            System.out.println("这个数是偶数");
        }else{
            System.out.println("这个数是奇数");
        }
    }
}

  

8.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。

package School.Day4;
import java.util.Scanner;
public class Test08 {
    public static void main(String[] args){
        Scanner s = new Scanner(System.in);
        System.out.print("输入变量: ");
        int x = s.nextInt();
        switch(x){
            case 1:
                x = 1;
                break;
            case 5:
                x = 5;
                break;
            case 10:
                x = 10;
                break;
            default:
                System.out.println("none");
                return;
        }
        System.out.println("变量是: " + x);
    }
}

  

9.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)
package School.Day4;
import java.util.Scanner;
public class Test09 {
    public static void main(String[] args) {
        System.out.print("输入一个数: ");
        Scanner s = new Scanner(System.in);
        int x = s.nextInt();
        if (x%5==0 && x%6==0) {
            System.out.println(x + "可以被5和6整除");
        }else if (x%5==0) {
            System.out.println(x + "可以被5整除");
        }else if (x%6==0) {
            System.out.println(x + "可以被6整除");
        }else{
            System.out.println(x + "不可以被5或者6整除");
        }
    }
}

  


 

posted @ 2021-03-26 16:58  李芊  阅读(64)  评论(0编辑  收藏  举报