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<?php $youtube = "https://www.youtube.com/watch?v=9g30pPikveg&feature=youtu.be"; preg_match("/^(?:http(?:s)?:\/\/)?(?:www\.)?(?:m\.)?(?:youtu\.be\/|youtube\.com\/(?:(?:watch)?\?(?:.*&)?v(?:i)?=|(?:embed|v|vi|user)\/))([^\?&\"'>]+)/", $youtube, $matches); echo $matches[1];

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