public static void main ( String [ ] $ ) {
  int n = scanner . nextInt ( ) , m = scanner . nextInt ( ) ;
  List < Integer > list = IntStream . range ( 0 , m ) . map ( i -> scanner . nextInt ( ) ) . boxed ( ) . collect ( Collectors . toList ( ) ) ;
  Collections . reverse ( list ) ;
  Stream . concat ( list . stream ( ) , IntStream . rangeClosed ( 1 , n ) . boxed ( ) ) . distinct ( ) . forEach ( System . out :: println ) ;
}

public static void main ( String [ ] $ ) { int n = scanner . nextInt ( ) , m = scanner . nextInt ( ) ; List < Integer > list = IntStream . range ( 0 , m ) . map ( i -> scanner . nextInt ( ) ) . boxed ( ) . collect ( Collectors . toList ( ) ) ; Collections . reverse ( list ) ; Stream . concat ( list . stream ( ) , IntStream . rangeClosed ( 1 , n ) . boxed ( ) ) . distinct ( ) . forEach ( System . out :: println ) ; }
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