3v4l.org

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<?php $array = array("person1" => array(0 => array('k1'=>'v1', 'k2'=>'v2'), 1 => array('k1'=>'v1', 'k2'=>'v2')), "person2" => array(0 => array('k1'=>'v1', 'k2'=>'v2'), 1 => array('k1'=>'v1', 'k2'=>'v2'))); reset($array); $first_key = key($array); echo $first_key;

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