public static void main ( String args [ ] ) {
  Scanner sc = new Scanner ( System . in ) ;
  String ava = sc . next ( ) ;
  String gar = sc . next ( ) ;
  HashMap < Character , Integer > mapava = new HashMap < > ( ) ;
  HashMap < Character , Integer > mapgar = new HashMap < > ( ) ;
  for ( int i = 0 ;
  i < ava . length ( ) ;
  i ++ ) {
    if ( ! mapava . containsKey ( ava . charAt ( i ) ) ) mapava . put ( ava . charAt ( i ) , 1 ) ;
    else mapava . put ( ava . charAt ( i ) , mapava . get ( ava . charAt ( i ) ) + 1 ) ;
  }
  for ( int i = 0 ;
  i < gar . length ( ) ;
  i ++ ) {
    if ( ! mapgar . containsKey ( gar . charAt ( i ) ) ) mapgar . put ( gar . charAt ( i ) , 1 ) ;
    else mapgar . put ( gar . charAt ( i ) , mapgar . get ( gar . charAt ( i ) ) + 1 ) ;
  }
  int ans = 0 ;
  for ( Map . Entry < Character , Integer > mape : mapgar . entrySet ( ) ) {
    if ( mapava . containsKey ( mape . getKey ( ) ) ) ans += Math . min ( mape . getValue ( ) , mapava . get ( mape . getKey ( ) ) ) ;
    else {
      ans = 0 ;
      break ;
    }
  }
  if ( ans == 0 ) System . out . println ( - 1 ) ;
  else System . out . println ( ans ) ;
}

public static void main ( String args [ ] ) { Scanner sc = new Scanner ( System . in ) ; String ava = sc . next ( ) ; String gar = sc . next ( ) ; HashMap < Character , Integer > mapava = new HashMap < > ( ) ; HashMap < Character , Integer > mapgar = new HashMap < > ( ) ; for ( int i = 0 ; i < ava . length ( ) ; i ++ ) { if ( ! mapava . containsKey ( ava . charAt ( i ) ) ) mapava . put ( ava . charAt ( i ) , 1 ) ; else mapava . put ( ava . charAt ( i ) , mapava . get ( ava . charAt ( i ) ) + 1 ) ; } for ( int i = 0 ; i < gar . length ( ) ; i ++ ) { if ( ! mapgar . containsKey ( gar . charAt ( i ) ) ) mapgar . put ( gar . charAt ( i ) , 1 ) ; else mapgar . put ( gar . charAt ( i ) , mapgar . get ( gar . charAt ( i ) ) + 1 ) ; } int ans = 0 ; for ( Map . Entry < Character , Integer > mape : mapgar . entrySet ( ) ) { if ( mapava . containsKey ( mape . getKey ( ) ) ) ans += Math . min ( mape . getValue ( ) , mapava . get ( mape . getKey ( ) ) ) ; else { ans = 0 ; break ; } } if ( ans == 0 ) System . out . println ( - 1 ) ; else System . out . println ( ans ) ; }
(method_declaration (modifiers) type: (void_type) name: (identifier) parameters: (formal_parameters (formal_parameter type: (type_identifier) name: (identifier) dimensions: (dimensions))) 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: (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) (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: (generic_type (type_identifier) (type_arguments (type_identifier) (type_identifier))) declarator: (variable_declarator name: (identifier) value: (object_creation_expression type: (generic_type (type_identifier) (type_arguments)) 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 (if_statement condition: (parenthesized_expression (unary_expression operand: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (identifier))))))) consequence: (expression_statement (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (identifier))) (decimal_integer_literal)))) alternative: (expression_statement (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (identifier))) (binary_expression left: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (identifier))))) right: (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: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list))) update: (update_expression (identifier)) body: (block (if_statement condition: (parenthesized_expression (unary_expression operand: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (identifier))))))) consequence: (expression_statement (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (identifier))) (decimal_integer_literal)))) alternative: (expression_statement (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (identifier))) (binary_expression left: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (identifier))))) right: (decimal_integer_literal)))))))) (local_variable_declaration type: (integral_type) declarator: (variable_declarator name: (identifier) value: (decimal_integer_literal))) (enhanced_for_statement type: (generic_type (scoped_type_identifier (type_identifier) (type_identifier)) (type_arguments (type_identifier) (type_identifier))) name: (identifier) value: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list)) body: (block (if_statement condition: (parenthesized_expression (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (method_invocation object: (identifier) name: (identifier) arguments: (argument_list))))) consequence: (expression_statement (assignment_expression left: (identifier) right: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (method_invocation object: (identifier) name: (identifier) arguments: (argument_list)) (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (method_invocation object: (identifier) name: (identifier) arguments: (argument_list)))))))) alternative: (block (expression_statement (assignment_expression left: (identifier) right: (decimal_integer_literal))) (break_statement))))) (if_statement condition: (parenthesized_expression (binary_expression left: (identifier) right: (decimal_integer_literal))) consequence: (expression_statement (method_invocation object: (field_access object: (identifier) field: (identifier)) name: (identifier) arguments: (argument_list (unary_expression operand: (decimal_integer_literal))))) alternative: (expression_statement (method_invocation object: (field_access object: (identifier) field: (identifier)) name: (identifier) arguments: (argument_list (identifier)))))))