public static void main ( String [] args ) throws IOException {
	     BufferedReader bf= new BufferedReader ( new InputStreamReader ( System.in )) ;
	     System.out.print ( "Masukan Bilangan Binernya = " ) ;
	     String str = bf.readLine () ;
	     long num = Long.parseLong ( str ) ;
	     long rem;
	     while ( num > 0 ){
	       rem = num % 10 ;
	       num = num / 10 ;
	       if ( rem != 0 && rem != 1 ){
	         System.out.println ( "Ini bukan bilangan biner" ) ;
	         System.out.println ( "Silahkan Coba lagi" ) ;
	         System.exit ( 0 ) ;
	       }
	     }
	     int i= Integer.parseInt ( str, 2 ) ;
	     System.out.println ( "Desimalnya : " + i ) ;
	   }