function reverse_r($str) { if (strlen($str) > 0) { echo substr($str, 1), PHP_EOL; reverse_r(substr($str, 1)); } echo substr($str, 0, 1); return; } reverse_r('Hello') reverse_r('ello'); reverse_r('llo'); reverse_r('lo'); reverse_r('o'); reverse_r(''); reverse_r('Hello');
宠物免费领养小程序,欢迎来踩