第四周作业

1.输入年份月份，输出该月的天数

package qq;

import java.util.Scanner;

public class kk {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        Scanner input=new Scanner(System.in);
        System.out.println("输入年份");
        int year=input.nextInt();
        System.out.println("输入月份");
        int y=input.nextInt();
        int days=31;
        switch(y) {
        case 4:
        case 6:
        case 9:
        case 11:
        days=30;
        break;
        case 2:
            if((year%4==0&&year%100!=0)||year%400==0){
            days=29;
            }else {
                days=28;
            }
            break;
        }
        System.out.println("该月有"+days+"天");

    }

}

 

 

 2.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 zzx;

public class sad {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        int fen=90;
        int grade=fen/10;
        switch(grade) {
        case 10:
        case 9:
            System.out.println("A");
            break;
        case 8:
            System.out.println("B");
            break;
        case 7:
            System.out.println("C");
            break;
        case 6:
            System.out.println("D");
            break;
        case 5:
        case 4:    
        case 3:
        case 2:    
        case 1:    
        case 0:
            System.out.println("E");
            break;
            
            
            
            
            }
        }
        

    }

 

 

 3.输入一个数，判断是奇数还是偶数

package qq;

import java.util.Scanner;

public class qqw {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        Scanner input=new Scanner(System.in);
        System.out.println("请输入一个数");
        int a=input.nextInt();
        if(a==0) {
            System.out.println("既不是奇数也不是偶数");
        }else if(a%2==0) {
            System.out.println("偶数");
        }else if(a%2!=0) {
            System.out.println("奇数");
        }

    }

}

 

 

 4.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 iii;

import java.util.Scanner;

public class dd {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        Scanner input=new Scanner(System.in);
        System.out.println("输入一个变量x");
        int x=input.nextInt();
        if(x==1) {
            System.out.println("x=1");
        }else if(x==5){
            System.out.println("x=5");
        }else if(x==10) {
            System.out.println("x=10");
        }else {
            System.out.println("x=none");
        }
        

    }

}

 

 

 5.判断一个数字是否能被5或6同时整除，或只能被5整除，或只能被6整除，或不能被5和6整除

package iii;

import java.util.Scanner;

public class qq {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        Scanner input=new Scanner(System.in);
        System.out.println("请输入一个数");
        int a=input.nextInt();
        if(a%5==0&&a%6==0) {
            System.out.println("能被5和6同时整除");
        }else if(a%5==0) {
            System.out.println("能被5整除");
        }else if(a%6==0) {
            System.out.println("能被6整除");
        }else if(a%5!=0&&a%6!=0) {
            System.out.println("不能被5和6整除");
        }

    }

}

 

 

 6.输入一个年份，判断是否是闰年

package iii;

import java.util.Scanner;

public class z {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        Scanner input=new Scanner(System.in);
        System.out.println("输入一个年份");
        int year=input.nextInt();
        if((year%4==0&&year%100!=0)||year%400==0) {
            System.out.println("今年是闰年");
        }else {
            System.out.println("今年不是闰年");
        }

    }

}

 

 

  7.输入一个四位会员卡号，如果百位数是随机数，就输出幸运会员，否则输出不是

package iii;

import java.util.Random;
import java.util.Scanner;

public class jkj {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        Scanner input=new Scanner(System.in);
        System.out.println("请输入会员号");
        int hao=input.nextInt();
        int x;
        x=hao/100%10;
        Random r=new Random();
        int a=r.nextInt(10);
        System.out.println("hao");
        if(a==hao) {
            System.out.println("是幸运会员");
        }else {
            System.out.println("不是幸运会员");
        }
        

    }

}

 

 

 8.已知函数，输入x的值，输出对应y的值   x+3（x>0）      y=0(x=0)            x*2-1(x<0)

package iii;

import java.util.Scanner;

public class yu {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        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);
        }
        

    }

}

 

 9.输入三个数，判断是否能构成三角形

package iii;

import java.util.Scanner;

public class qw {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        Scanner input=new Scanner(System.in);
        System.out.println("输入三边长度");
        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 if(a+b<=c || a+c<=b ||                                                                                                     b+c<=a) {
            System.out.println("不能构成三角形");
        }

    }

}