public static void main ( String [ ] args ) throws IOException {
  int n = Reader . nextInt ( ) ;
  int res = 4 ;
  if ( ( n & 1 ) == 0 ) {
    while ( n > 2 ) {
      res += n + 1 ;
      n -= 2 ;
    }
  }
  else {
    while ( n > 1 ) {
      res += 2 * ( n + 1 ) ;
      n -= 2 ;
    }
  }
  System . out . println ( res ) ;
}

public static void main ( String [ ] args ) throws IOException { int n = Reader . nextInt ( ) ; int res = 4 ; if ( ( n & 1 ) == 0 ) { while ( n > 2 ) { res += n + 1 ; n -= 2 ; } } else { while ( n > 1 ) { res += 2 * ( n + 1 ) ; n -= 2 ; } } System . out . println ( res ) ; }
(method_declaration (modifiers) type: (void_type) name: (identifier) parameters: (formal_parameters (formal_parameter type: (array_type element: (type_identifier) dimensions: (dimensions)) name: (identifier))) (throws (type_identifier)) 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) value: (decimal_integer_literal))) (if_statement condition: (parenthesized_expression (binary_expression left: (parenthesized_expression (binary_expression left: (identifier) right: (decimal_integer_literal))) right: (decimal_integer_literal))) consequence: (block (while_statement condition: (parenthesized_expression (binary_expression left: (identifier) right: (decimal_integer_literal))) body: (block (expression_statement (assignment_expression left: (identifier) right: (binary_expression left: (identifier) right: (decimal_integer_literal)))) (expression_statement (assignment_expression left: (identifier) right: (decimal_integer_literal)))))) alternative: (block (while_statement condition: (parenthesized_expression (binary_expression left: (identifier) right: (decimal_integer_literal))) body: (block (expression_statement (assignment_expression left: (identifier) right: (binary_expression left: (decimal_integer_literal) right: (parenthesized_expression (binary_expression left: (identifier) right: (decimal_integer_literal)))))) (expression_statement (assignment_expression left: (identifier) right: (decimal_integer_literal))))))) (expression_statement (method_invocation object: (field_access object: (identifier) field: (identifier)) name: (identifier) arguments: (argument_list (identifier))))))