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<?php
$subject = "11D 06:06:22H";
$data = DateTime::createFromFormat('d? H:i:s?', $subject);
$result = sprintf(
'%d dni %d godzin %d minut %d sekund',
$data->format("d"),
$data->format("H"),
$data->format("i"),
$data->format("s")
);