public static void main ( String [ ] args ) {
  int n = sc . nextInt ( ) ;
  long [ ] a = new long [ 2 * n ] ;
  long ans = 0 ;
  long fn = pow ( fact ( n ) , mod - 2 ) ;
  long count = fact ( 2 * n ) ;
  for ( int i = 0 ;
  i < 2 * n ;
  i ++ ) {
    a [ i ] = sc . nextLong ( ) ;
  }
  Arrays . sort ( a ) ;
  for ( int i = 0 ;
  i < n ;
  i ++ ) {
    ans = mod ( ans + a [ 2 * n - i - 1 ] - a [ i ] ) ;
  }
  ans = mod ( count * ans ) ;
  ans = mod ( ans * fn ) ;
  ans = mod ( ans * fn ) ;
  System . out . println ( ans ) ;
}

public static void main ( String [ ] args ) { int n = sc . nextInt ( ) ; long [ ] a = new long [ 2 * n ] ; long ans = 0 ; long fn = pow ( fact ( n ) , mod - 2 ) ; long count = fact ( 2 * n ) ; for ( int i = 0 ; i < 2 * n ; i ++ ) { a [ i ] = sc . nextLong ( ) ; } Arrays . sort ( a ) ; for ( int i = 0 ; i < n ; i ++ ) { ans = mod ( ans + a [ 2 * n - i - 1 ] - a [ i ] ) ; } ans = mod ( count * ans ) ; ans = mod ( ans * fn ) ; ans = mod ( ans * fn ) ; System . out . println ( ans ) ; }
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