static int cost ( String str ) {
  int len = str . length ( ) ;
  int res = 0 ;
  for ( int i = 0 , j = len - 1 ;
  i < j ;
  i ++ , j -- ) if ( str . charAt ( i ) != str . charAt ( j ) ) res += Math . min ( str . charAt ( i ) , str . charAt ( j ) ) - 'a' + 1 ;
  return res ;
}

static int cost ( String str ) { int len = str . length ( ) ; int res = 0 ; for ( int i = 0 , j = len - 1 ; i < j ; i ++ , j -- ) if ( str . charAt ( i ) != str . charAt ( j ) ) res += Math . min ( str . charAt ( i ) , str . charAt ( j ) ) - ' a ' + 1 ; return res ; }
(method_declaration (modifiers) type: (integral_type) name: (identifier) parameters: (formal_parameters (formal_parameter type: (type_identifier) name: (identifier))) body: (block (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: (decimal_integer_literal))) (for_statement init: (local_variable_declaration type: (integral_type) declarator: (variable_declarator name: (identifier) value: (decimal_integer_literal)) declarator: (variable_declarator name: (identifier) value: (binary_expression left: (identifier) right: (decimal_integer_literal)))) condition: (binary_expression left: (identifier) right: (identifier)) update: (update_expression (identifier)) update: (update_expression (identifier)) body: (if_statement condition: (parenthesized_expression (binary_expression left: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (identifier))) right: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (identifier))))) consequence: (expression_statement (assignment_expression left: (identifier) right: (binary_expression left: (binary_expression left: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (identifier))) (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (identifier))))) right: (character_literal)) right: (decimal_integer_literal)))))) (return_statement (identifier))))