Online PHP editor | refs for 8EBmC

<?php $str = 'fxs_124024574287414=base_domain=.example.com; datr=KWHazxXEIkldzBaVq_of--syv5; csrftoken=szcwad; ds_user_id=219132; mid=XN4bpAAEAAHOyBRR4V17xfbaosyN; sessionid=14811313756%12fasda%3A27; rur=VLL;'; echo preg_match('~ds_user_id=\K\d+~', $str, $out) ? $out[0] : 'no match';