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import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.nio.ByteBuffer;
import java.nio.ByteOrder;
import java.nio.FloatBuffer;
import java.nio.channels.FileChannel;
import java.nio.channels.FileChannel.MapMode;

/**
 *
 * @author tonyj
 */
public class Main
{
   public static void main(String[] args) throws IOException
   {
      File file = new File(args[0]);
      FileInputStream in = new FileInputStream(file);
      FileChannel channel = in.getChannel();
      ByteBuffer buffer = channel.map(MapMode.READ_ONLY,0,file.length());
      buffer.order(ByteOrder.BIG_ENDIAN);
      final int size = buffer.getInt();
      FloatBuffer floats = buffer.asFloatBuffer();
      
      int nAccept = 0;
      float eCut = (float) Math.exp(4);
      long start = System.currentTimeMillis();
      for (int i=0; i<4*size; i += 4)
      {
         float time = floats.get(i);
         if (time < 20000 || time > 70000) continue;
         float energy = floats.get(i+1);
         if (energy < eCut) continue;
         float rightAscension = floats.get(i+2);
         float declination = floats.get(i+3);
         float dRA = rightAscension-180;
         float dDec = declination-0;
         if (dRA*dRA + dDec*dDec > 15*15) continue;
         nAccept++;
         //System.out.printf("%g %g %g %g\n",time,energy,dRA,dDec);
      }
      long stop = System.currentTimeMillis();
      System.out.println("Elapsed "+(stop-start)+"ms");
      System.out.println("Accepted "+nAccept+"/"+size);
      in.close();
      
   }
   
}