public static void main ( String [ ] args ) {
  Scanner sc = new Scanner ( System . in ) ;
  String s = sc . next ( ) ;
  String [ ] str = s . split ( "" ) ;
  List < String > listA = Arrays . asList ( str ) ;
  List < String > listB = new ArrayList < String > ( new HashSet < > ( listA ) ) ;
  if ( listA . size ( ) == listB . size ( ) ) {
    System . out . println ( "yes" ) ;
  }
  else {
    System . out . println ( "no" ) ;
  }
}

public static void main ( String [ ] args ) { Scanner sc = new Scanner ( System . in ) ; String s = sc . next ( ) ; String [ ] str = s . split ( " " ) ; List < String > listA = Arrays . asList ( str ) ; List < String > listB = new ArrayList < String > ( new HashSet < > ( listA ) ) ; if ( listA . size ( ) == listB . size ( ) ) { System . out . println ( " yes " ) ; } else { System . out . println ( " no " ) ; } }
(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 (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: (type_identifier) declarator: (variable_declarator name: (identifier) value: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list)))) (local_variable_declaration type: (array_type element: (type_identifier) dimensions: (dimensions)) declarator: (variable_declarator name: (identifier) value: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (string_literal))))) (local_variable_declaration type: (generic_type (type_identifier) (type_arguments (type_identifier))) declarator: (variable_declarator name: (identifier) value: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (identifier))))) (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 (type_identifier))) arguments: (argument_list (object_creation_expression type: (generic_type (type_identifier) (type_arguments)) arguments: (argument_list (identifier))))))) (if_statement condition: (parenthesized_expression (binary_expression left: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list)) right: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list)))) consequence: (block (expression_statement (method_invocation object: (field_access object: (identifier) field: (identifier)) name: (identifier) arguments: (argument_list (string_literal))))) alternative: (block (expression_statement (method_invocation object: (field_access object: (identifier) field: (identifier)) name: (identifier) arguments: (argument_list (string_literal))))))))