HW5.27

 public class Solution
 {
     public static void main(String[] args)
     {
         int totalCount = 0;
         int lineCount = 0;
         int i = 2;

         while(true)
         {
             if(isPrime(i) && (isPrime(getReverse(i))))
             {
                 System.out.printf("%d\t", i);
                 totalCount++;
                 lineCount++;
             }

             i++;

             if(lineCount == 10)
             {
                 lineCount = 0;
                 System.out.println();
             }

             if(totalCount == 100)
                 break;
         }
     }

     public static boolean isPrime(int number)
     {
         if(number == 1)
             return false;
         else if(number == 2)
             return true;
         else
         {
             for(int i = 2; i < number; i++)
             {
                 if(number % i == 0)
                     return false;
             }
             return true;
         }
     }

     public static int getReverse(int number)
     {
         String str = "";
         if(number < 10)
             str += number;
         else
             str += number % 10 + "" + getReverse(number / 10);
         return Integer.parseInt(str);
     }
 }