static String minimize ( String str ) {
  String mstr = " " ;
  int l , i , flagchar [ ] = new int [ 26 ] ;
  char ch ;
  l = str . length ( ) ;
  for ( i = 0 ;
  i < str . length ( ) ;
  i ++ ) {
    ch = str . charAt ( i ) ;
    if ( flagchar [ ch - 97 ] == 0 ) {
      mstr = mstr + ch ;
      flagchar [ ch - 97 ] = 1 ;
    }
  }
  return mstr ;
}

static String minimize ( String str ) { String mstr = " ▁ " ; int l , i , flagchar [ ] = new int [ 26 ] ; char ch ; l = str . length ( ) ; for ( i = 0 ; i < str . length ( ) ; i ++ ) { ch = str . charAt ( i ) ; if ( flagchar [ ch - 97 ] == 0 ) { mstr = mstr + ch ; flagchar [ ch - 97 ] = 1 ; } } return mstr ; }
(method_declaration (modifiers) type: (type_identifier) name: (identifier) parameters: (formal_parameters (formal_parameter type: (type_identifier) name: (identifier))) body: (block (local_variable_declaration type: (type_identifier) declarator: (variable_declarator name: (identifier) value: (string_literal))) (local_variable_declaration type: (integral_type) declarator: (variable_declarator name: (identifier)) declarator: (variable_declarator name: (identifier)) declarator: (variable_declarator name: (identifier) dimensions: (dimensions) value: (array_creation_expression type: (integral_type) dimensions: (dimensions_expr (decimal_integer_literal))))) (local_variable_declaration type: (integral_type) declarator: (variable_declarator name: (identifier))) (expression_statement (assignment_expression left: (identifier) right: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list)))) (for_statement init: (assignment_expression left: (identifier) right: (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 (assignment_expression left: (identifier) right: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (identifier))))) (if_statement condition: (parenthesized_expression (binary_expression left: (array_access array: (identifier) index: (binary_expression left: (identifier) right: (decimal_integer_literal))) right: (decimal_integer_literal))) consequence: (block (expression_statement (assignment_expression left: (identifier) right: (binary_expression left: (identifier) right: (identifier)))) (expression_statement (assignment_expression left: (array_access array: (identifier) index: (binary_expression left: (identifier) right: (decimal_integer_literal))) right: (decimal_integer_literal))))))) (return_statement (identifier))))