public static void main ( String [ ] args ) {
  Scanner scan = new Scanner ( System . in ) ;
  int n = scan . nextInt ( ) ;
  int k = scan . nextInt ( ) ;
  scan . nextLine ( ) ;
  String s = scan . nextLine ( ) ;
  Set < Character > sch = new HashSet < Character > ( ) ;
  for ( int i = 0 ;
  i < s . length ( ) ;
  i ++ ) {
    sch . add ( s . charAt ( i ) ) ;
  }
  List < Character > li = new ArrayList < Character > ( sch ) ;
  Collections . sort ( li ) ;
  ;
}

public static void main ( String [ ] args ) { Scanner scan = new Scanner ( System . in ) ; int n = scan . nextInt ( ) ; int k = scan . nextInt ( ) ; scan . nextLine ( ) ; String s = scan . nextLine ( ) ; Set < Character > sch = new HashSet < Character > ( ) ; for ( int i = 0 ; i < s . length ( ) ; i ++ ) { sch . add ( s . charAt ( i ) ) ; } List < Character > li = new ArrayList < Character > ( sch ) ; Collections . sort ( li ) ; ; }
(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: (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: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list)))) (expression_statement (method_invocation object: (identifier) name: (identifier) arguments: (argument_list))) (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: (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)))) (for_statement init: (local_variable_declaration type: (integral_type) declarator: (variable_declarator name: (identifier) value: (decimal_integer_literal))) condition: (binary_expression left: (identifier) right: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list))) update: (update_expression (identifier)) body: (block (expression_statement (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (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 (identifier))))) (expression_statement (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (identifier))))))