static int countSubsets ( int arr [ ] , int n ) {
  HashSet < Integer > us = new HashSet < > ( ) ;
  int even_count = 0 ;
  for ( int i = 0 ;
  i < n ;
  i ++ ) if ( arr [ i ] % 2 == 0 ) us . add ( arr [ i ] ) ;
  even_count = us . size ( ) ;
  return ( int ) ( Math . pow ( 2 , even_count ) - 1 ) ;
}

static int countSubsets ( int arr [ ] , int n ) { HashSet < Integer > us = new HashSet < > ( ) ; int even_count = 0 ; for ( int i = 0 ; i < n ; i ++ ) if ( arr [ i ] % 2 == 0 ) us . add ( arr [ i ] ) ; even_count = us . size ( ) ; return ( int ) ( Math . pow ( 2 , even_count ) - 1 ) ; }
(method_declaration (modifiers) type: (integral_type) name: (identifier) parameters: (formal_parameters (formal_parameter type: (integral_type) name: (identifier) dimensions: (dimensions)) (formal_parameter type: (integral_type) name: (identifier))) body: (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)))) (local_variable_declaration type: (integral_type) declarator: (variable_declarator name: (identifier) value: (decimal_integer_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: (identifier)) update: (update_expression (identifier)) body: (if_statement condition: (parenthesized_expression (binary_expression left: (binary_expression left: (array_access array: (identifier) index: (identifier)) right: (decimal_integer_literal)) right: (decimal_integer_literal))) consequence: (expression_statement (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (array_access array: (identifier) index: (identifier))))))) (expression_statement (assignment_expression left: (identifier) right: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list)))) (return_statement (cast_expression type: (integral_type) value: (parenthesized_expression (binary_expression left: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (decimal_integer_literal) (identifier))) right: (decimal_integer_literal)))))))