第一次java作业

package com.wsy.work;

public class JudgeNumber {

 public static void main(String[] args) {
     int a = 5;
     if(a % 2 == 0)
     {
          System.out.println(a+"是偶数");
     }
     else
     {
         System.out.println(a+"是奇数");
     }

 }

}

package com.wsy.work;
import java.math.BigDecimal;
import java.util.Scanner;
public class Circle {

 public static void main(String[] args) {
     BigDecimal PI  = new BigDecimal("3.14");
     Scanner in = new Scanner(System.in);
     System.out.print("请输入圆的半径:");
    BigDecimal ridius = new BigDecimal(in.nextLine());
     BigDecimal s = ridius.multiply(ridius).multiply(PI);
     System.out.println("圆的面积为："+s);
     in.close();
 }

}

package com.wsy.work;
import java.util.Scanner;
public class EncryptionDevice {

  public static void main(String[] args) {
      Scanner in = new Scanner(System.in);
     int number = Integer.parseInt(in.nextLine());
   double result = (number*10+5)/2+3.14159;
      System.out.println("加密结果为:"+result);
 }

}

package com.wsy.work;

public class Work4 {

  public static void main(String[] args) {
      final int CHICKEN = 100;
      final int MONEY = 100;
      for(int i = 0; i<=20; i++)
     {
         for(int j = 0; j<=33; j++)
         {
             for(int k = 0; k<=300; k=k+3)
             {
                 if(i*5+j*3+k/3 == MONEY && i+j+k == CHICKEN)
                 {
                     System.out.println("公鸡:"+i);
                     System.out.println("母鸡:"+j);
                     System.out.println("公鸡:"+k);
                     System.out.println("==================================================");                     }
             }
             
        }
        
     }
 }

}

package com.wsy.work;

public class Work5 {

 public static void main(String[] args) {
     int number;
     int count = 0;
     for(int i = 1; i<=4; i++)
     {
         for(int j =1; j<=4; j++)
         {
             for(int k = 1; k<=4; k++)
             {
                 if(i != j && i != k && j!=k)
                 {
                     count++;
                     number = i*100+j*10+k;
                     System.out.println(number);
                 }
            }
             
         }
        
     }
     System.out.println("======================================================");
     System.out.println("不重复的数字总共有:"+count+"个");
     
 }

}

package com.wsy.work;
import java.util.Scanner;
public class IsPrime {

public static void main(String[] args) {
     boolean isPrime = true;
    Scanner in = new Scanner(System.in);
    int number = Integer.parseInt(in.nextLine());
    if(number == 1)
     {
        isPrime = false ;
     }
     for(int i = 2; i<=Math.sqrt(number); i++)
     {
        if(number % i ==0)
        {                 isPrime = false ;
             break;
         }
    }
     if(isPrime)
     {
        System.out.println(number+"是素数");
     }
     else
     {
         System.out.println(number+"不是素数");
     }
     in.close();
 }