import java.io.*;
import java.util.Scanner;


 
public class ArrayDoubling
{
   public static void main(String[] args) throws IOException
   {
      File inpFile = new File( "ArrayDoubling.inp" );
      Scanner inp = new Scanner ( inpFile );
 
      double[] a = new double[1];
      double   x;
      int      n;               // Number of items

      n = 0;

      while ( inp.hasNextDouble() )
      {
         x = inp.nextDouble();
         System.out.println("Data item " + n + ": " + x);

         if ( n == a.length )
         {
            /* ==========================================
               Array is full... increase its size first
               ========================================== */
            System.out.println("      Array is full... increase size to: " 
			+ 2*a.length );

            double[] h;  // help variable to make a bigger array
            h = new double[ 2*a.length ];  // make aray twice as big

            for ( int i = 0; i < a.length; i++ )
                h[i] = a[i];               // copy old values

            a = h;                         // make "a" point to new array
          }

          /* ==========================================
             Here, the array will surely have space
             ========================================== */
          a[n] = x;   // Put number read in a[n]
          n++;        // Go to next array position
          System.out.println("   stored in a[" + n + "]");
      }

      /* ==========================================
         Done, print values read
         ========================================== */
      for ( int i = 0; i < a.length; i++ )
         System.out.println( a[i] );
   }
}