public static void main ( String [ ] args ) {
  try {
    FastScanner in = new FastScanner ( ) ;
    PrintWriter out = new PrintWriter ( System . out ) ;
    int t = in . nextInt ( ) ;
    while ( t -- > 0 ) {
      int n = in . nextInt ( ) ;
      int A [ ] = in . readArray ( n ) ;
      StringBuilder sb = new StringBuilder ( ) ;
      int ct = 2 ;
      sb . append ( A [ 0 ] + " " ) ;
      for ( int i = 1 ;
      i < n - 1 ;
      i ++ ) {
        if ( ( A [ i ] > A [ i - 1 ] && A [ i ] > A [ i + 1 ] ) || ( A [ i ] < A [ i - 1 ] && A [ i ] < A [ i + 1 ] ) ) {
          ct ++ ;
          sb . append ( A [ i ] + " " ) ;
        }
      }
      sb . append ( A [ n - 1 ] ) ;
      System . out . println ( ct ) ;
      System . out . println ( sb ) ;
    }
    out . flush ( ) ;
    out . close ( ) ;
  }
  catch ( Exception e ) {
    return ;
  }
}

public static void main ( String [ ] args ) { try { FastScanner in = new FastScanner ( ) ; PrintWriter out = new PrintWriter ( System . out ) ; int t = in . nextInt ( ) ; while ( t -- > 0 ) { int n = in . nextInt ( ) ; int A [ ] = in . readArray ( n ) ; StringBuilder sb = new StringBuilder ( ) ; int ct = 2 ; sb . append ( A [ 0 ] + " ▁ " ) ; for ( int i = 1 ; i < n - 1 ; i ++ ) { if ( ( A [ i ] > A [ i - 1 ] && A [ i ] > A [ i + 1 ] ) || ( A [ i ] < A [ i - 1 ] && A [ i ] < A [ i + 1 ] ) ) { ct ++ ; sb . append ( A [ i ] + " ▁ " ) ; } } sb . append ( A [ n - 1 ] ) ; System . out . println ( ct ) ; System . out . println ( sb ) ; } out . flush ( ) ; out . close ( ) ; } catch ( Exception e ) { return ; } }
(method_declaration (modifiers) type: (void_type) name: (identifier) parameters: (formal_parameters (formal_parameter type: (array_type element: (type_identifier) dimensions: (dimensions)) name: (identifier))) body: (block (try_statement body: (block (local_variable_declaration type: (type_identifier) declarator: (variable_declarator name: (identifier) value: (object_creation_expression type: (type_identifier) arguments: (argument_list)))) (local_variable_declaration type: (type_identifier) declarator: (variable_declarator name: (identifier) value: (object_creation_expression type: (type_identifier) arguments: (argument_list (field_access object: (identifier) field: (identifier)))))) (local_variable_declaration type: (integral_type) declarator: (variable_declarator name: (identifier) value: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list)))) (while_statement condition: (parenthesized_expression (binary_expression left: (update_expression (identifier)) right: (decimal_integer_literal))) body: (block (local_variable_declaration type: (integral_type) declarator: (variable_declarator name: (identifier) value: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list)))) (local_variable_declaration type: (integral_type) declarator: (variable_declarator name: (identifier) dimensions: (dimensions) value: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (identifier))))) (local_variable_declaration type: (type_identifier) declarator: (variable_declarator name: (identifier) value: (object_creation_expression type: (type_identifier) arguments: (argument_list)))) (local_variable_declaration type: (integral_type) declarator: (variable_declarator name: (identifier) value: (decimal_integer_literal))) (expression_statement (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (binary_expression left: (array_access array: (identifier) index: (decimal_integer_literal)) right: (string_literal))))) (for_statement init: (local_variable_declaration type: (integral_type) declarator: (variable_declarator name: (identifier) value: (decimal_integer_literal))) condition: (binary_expression left: (identifier) right: (binary_expression left: (identifier) right: (decimal_integer_literal))) update: (update_expression (identifier)) body: (block (if_statement condition: (parenthesized_expression (binary_expression left: (parenthesized_expression (binary_expression left: (binary_expression left: (array_access array: (identifier) index: (identifier)) right: (array_access array: (identifier) index: (binary_expression left: (identifier) right: (decimal_integer_literal)))) right: (binary_expression left: (array_access array: (identifier) index: (identifier)) right: (array_access array: (identifier) index: (binary_expression left: (identifier) right: (decimal_integer_literal)))))) right: (parenthesized_expression (binary_expression left: (binary_expression left: (array_access array: (identifier) index: (identifier)) right: (array_access array: (identifier) index: (binary_expression left: (identifier) right: (decimal_integer_literal)))) right: (binary_expression left: (array_access array: (identifier) index: (identifier)) right: (array_access array: (identifier) index: (binary_expression left: (identifier) right: (decimal_integer_literal)))))))) consequence: (block (expression_statement (update_expression (identifier))) (expression_statement (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (binary_expression left: (array_access array: (identifier) index: (identifier)) right: (string_literal))))))))) (expression_statement (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (array_access array: (identifier) index: (binary_expression left: (identifier) right: (decimal_integer_literal)))))) (expression_statement (method_invocation object: (field_access object: (identifier) field: (identifier)) name: (identifier) arguments: (argument_list (identifier)))) (expression_statement (method_invocation object: (field_access object: (identifier) field: (identifier)) name: (identifier) arguments: (argument_list (identifier)))))) (expression_statement (method_invocation object: (identifier) name: (identifier) arguments: (argument_list))) (expression_statement (method_invocation object: (identifier) name: (identifier) arguments: (argument_list)))) (catch_clause (catch_formal_parameter (catch_type (type_identifier)) name: (identifier)) body: (block (return_statement))))))