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// Pack.java - Demo of packing two ints into one long for efficiency.
// Written April 2000 by Wayne Pollock, Tampa Florida USA.

class Pack
{
public static void main ( String [] args )
{  int i = 17, j = 22;
   long mask = -1L >>> 32;  // 32 zeros, then 32 ones: 0x00000000FFFFFFFF
                            // Note the >>> operator shifts in zeros.
   if ( args.length == 2 )
   {  i = Integer.parseInt( args[0] );
      j = Integer.parseInt( args[1] );
   }
   long l = ( (long) i << 32 ) | ( j & mask );
   System.out.println( "packed values of " + i + " and " + j + ": " + l );
   int x = (int) ( l >> 32 );
   int y = (int) ( l & mask );
   System.out.println( "Extracted values are " + x + " and " + y );
}
}