public static void main ( String [ ] args ) {
  Scanner sc = new Scanner ( System . in ) ;
  int N = sc . nextInt ( ) ;
  int M = sc . nextInt ( ) ;
  ArrayList < Integer > odd = new ArrayList < > ( ) ;
  ArrayList < Integer > even = new ArrayList < > ( ) ;
  for ( int i = 0 ;
  i < M ;
  i ++ ) {
    int A = sc . nextInt ( ) ;
    if ( A % 2 == 0 ) even . add ( A ) ;
    else odd . add ( A ) ;
  }
  if ( odd . size ( ) > 2 ) {
    System . out . println ( "Impossible" ) ;
  }
  else {
    ArrayList < Integer > list = new ArrayList < > ( ) ;
    if ( odd . size ( ) > 0 ) list . add ( odd . get ( 0 ) ) ;
    list . addAll ( even ) ;
    if ( odd . size ( ) > 1 ) list . add ( odd . get ( 1 ) ) ;
    printList ( list ) ;
    if ( list . size ( ) == 1 ) {
      if ( list . get ( 0 ) > 1 ) {
        list . set ( 0 , list . get ( 0 ) - 1 ) ;
        list . add ( 1 ) ;
      }
    }
    else {
      list . set ( 0 , list . get ( 0 ) - 1 ) ;
      list . set ( list . size ( ) - 1 , list . get ( list . size ( ) - 1 ) - 1 ) ;
      list . add ( 1 , 2 ) ;
      if ( list . get ( 0 ) == 0 ) list . remove ( 0 ) ;
      if ( list . get ( list . size ( ) - 1 ) == 0 ) list . remove ( list . size ( ) - 1 ) ;
    }
    System . out . println ( list . size ( ) ) ;
    printList ( list ) ;
  }
  sc . close ( ) ;
}

public static void main ( String [ ] args ) { Scanner sc = new Scanner ( System . in ) ; int N = sc . nextInt ( ) ; int M = sc . nextInt ( ) ; ArrayList < Integer > odd = new ArrayList < > ( ) ; ArrayList < Integer > even = new ArrayList < > ( ) ; for ( int i = 0 ; i < M ; i ++ ) { int A = sc . nextInt ( ) ; if ( A % 2 == 0 ) even . add ( A ) ; else odd . add ( A ) ; } if ( odd . size ( ) > 2 ) { System . out . println ( " Impossible " ) ; } else { ArrayList < Integer > list = new ArrayList < > ( ) ; if ( odd . size ( ) > 0 ) list . add ( odd . get ( 0 ) ) ; list . addAll ( even ) ; if ( odd . size ( ) > 1 ) list . add ( odd . get ( 1 ) ) ; printList ( list ) ; if ( list . size ( ) == 1 ) { if ( list . get ( 0 ) > 1 ) { list . set ( 0 , list . get ( 0 ) - 1 ) ; list . add ( 1 ) ; } } else { list . set ( 0 , list . get ( 0 ) - 1 ) ; list . set ( list . size ( ) - 1 , list . get ( list . size ( ) - 1 ) - 1 ) ; list . add ( 1 , 2 ) ; if ( list . get ( 0 ) == 0 ) list . remove ( 0 ) ; if ( list . get ( list . size ( ) - 1 ) == 0 ) list . remove ( list . size ( ) - 1 ) ; } System . out . println ( list . size ( ) ) ; printList ( list ) ; } sc . close ( ) ; }
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(variable_declarator name: (identifier) value: (object_creation_expression type: (generic_type (type_identifier) (type_arguments)) arguments: (argument_list)))) (local_variable_declaration type: (generic_type (type_identifier) (type_arguments (type_identifier))) declarator: (variable_declarator name: (identifier) value: (object_creation_expression type: (generic_type (type_identifier) (type_arguments)) arguments: (argument_list)))) (for_statement init: (local_variable_declaration type: (integral_type) declarator: (variable_declarator name: (identifier) value: (decimal_integer_literal))) condition: (binary_expression left: (identifier) right: (identifier)) update: (update_expression (identifier)) body: (block (local_variable_declaration type: (integral_type) declarator: (variable_declarator name: (identifier) value: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list)))) (if_statement condition: (parenthesized_expression (binary_expression left: (binary_expression left: (identifier) right: (decimal_integer_literal)) right: (decimal_integer_literal))) consequence: (expression_statement (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (identifier)))) alternative: (expression_statement (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (identifier))))))) (if_statement condition: (parenthesized_expression (binary_expression left: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list)) right: (decimal_integer_literal))) consequence: (block (expression_statement (method_invocation object: (field_access object: (identifier) field: (identifier)) name: (identifier) arguments: (argument_list (string_literal))))) alternative: (block (local_variable_declaration type: (generic_type (type_identifier) (type_arguments (type_identifier))) declarator: (variable_declarator name: (identifier) value: (object_creation_expression type: (generic_type (type_identifier) (type_arguments)) arguments: (argument_list)))) (if_statement condition: (parenthesized_expression (binary_expression left: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list)) right: (decimal_integer_literal))) consequence: (expression_statement (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (decimal_integer_literal))))))) (expression_statement (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (identifier)))) (if_statement condition: (parenthesized_expression (binary_expression left: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list)) right: (decimal_integer_literal))) consequence: (expression_statement (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (decimal_integer_literal))))))) (expression_statement (method_invocation name: (identifier) arguments: (argument_list (identifier)))) (if_statement condition: (parenthesized_expression (binary_expression left: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list)) right: (decimal_integer_literal))) consequence: (block (if_statement condition: (parenthesized_expression (binary_expression left: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (decimal_integer_literal))) right: (decimal_integer_literal))) consequence: (block (expression_statement (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (decimal_integer_literal) (binary_expression left: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (decimal_integer_literal))) right: (decimal_integer_literal))))) (expression_statement (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (decimal_integer_literal))))))) alternative: (block (expression_statement (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (decimal_integer_literal) (binary_expression left: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (decimal_integer_literal))) right: (decimal_integer_literal))))) (expression_statement (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (binary_expression left: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list)) right: (decimal_integer_literal)) (binary_expression left: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (binary_expression left: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list)) right: (decimal_integer_literal)))) right: (decimal_integer_literal))))) (expression_statement (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (decimal_integer_literal) (decimal_integer_literal)))) (if_statement condition: (parenthesized_expression (binary_expression left: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (decimal_integer_literal))) right: (decimal_integer_literal))) consequence: (expression_statement (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (decimal_integer_literal))))) (if_statement condition: (parenthesized_expression (binary_expression left: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (binary_expression left: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list)) right: (decimal_integer_literal)))) right: (decimal_integer_literal))) consequence: (expression_statement (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (binary_expression left: (method_invocation 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