public static void main ( String [ ] args ) throws IOException {
  BufferedReader br = new BufferedReader ( new InputStreamReader ( System . in ) ) ;
  int t = Integer . parseInt ( br . readLine ( ) ) ;
  while ( t -- > 0 ) {
    int n = Integer . parseInt ( br . readLine ( ) ) ;
    int [ ] hash = new int [ n + 1 ] ;
    int [ ] a = Arrays . stream ( br . readLine ( ) . split ( "\\s+" ) ) . mapToInt ( Integer :: parseInt ) . toArray ( ) ;
    List < Integer > perm = new ArrayList < > ( ) ;
    for ( final int value : a ) {
      if ( hash [ value ] == 0 ) {
        perm . add ( value ) ;
        hash [ value ] = 1 ;
      }
    }
    System . out . println ( perm . stream ( ) . map ( String :: valueOf ) . collect ( Collectors . joining ( " " ) ) ) ;
  }
}

public static void main ( String [ ] args ) throws IOException { BufferedReader br = new BufferedReader ( new InputStreamReader ( System . in ) ) ; int t = Integer . parseInt ( br . readLine ( ) ) ; while ( t -- > 0 ) { int n = Integer . parseInt ( br . readLine ( ) ) ; int [ ] hash = new int [ n + 1 ] ; int [ ] a = Arrays . stream ( br . readLine ( ) . split ( " \\ s + " ) ) . mapToInt ( Integer :: parseInt ) . toArray ( ) ; List < Integer > perm = new ArrayList < > ( ) ; for ( final int value : a ) { if ( hash [ value ] == 0 ) { perm . add ( value ) ; hash [ value ] = 1 ; } } System . out . println ( perm . stream ( ) . map ( String :: valueOf ) . collect ( Collectors . joining ( " ▁ " ) ) ) ; } }
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