Online PHP editor | refs for bC4LK

<?php $events = [ [ 'date' => '1st June', 'events' => [ [ 'location' => 'Venue A', 'name' => 'Pete', 'time' => '4.00pm' ], [ 'location' => 'Venue A', 'name' => 'John', 'time' => '4.30pm' ], [ 'location' => 'Venue B', 'name' => 'Chris', 'time' => '7.30pm' ], [ 'location' => 'Venue A', 'name' => 'Mark', 'time' => '8.00pm' ] ] ], [ 'date' => '2nd June', 'events' => [ [ 'location' => 'Venue B', 'name' => 'Fred', 'time' => '5.00pm' ], [ 'location' => 'Venue C', 'name' => 'Boris', 'time' => '6.00pm' ], [ 'location' => 'Venue A', 'name' => 'Rupert', 'time' => '7.00pm' ], [ 'location' => 'Venue A', 'name' => 'Davis', 'time' => '9.00pm' ] ] ] ]; $resultEvents = []; foreach ($events as ['date' => $date, 'events' => $dayEvents]) { $resultDayEvents = ['date' => $date, 'events' => []]; foreach ($dayEvents as ['location' => $location, 'name' => $name, 'time' => $time]) { $attendee = ['name' => $name, 'time' => $time]; if ($location === ($previousLocation ?? null)) { $resultDayEvents['events'][array_key_last($resultDayEvents['events'])]['attendees'][] = $attendee; } else { $resultDayEvents['events'][] = ['location' => $location, 'attendees' => [$attendee]]; } $previousLocation = $location; } $resultEvents[] = $resultDayEvents; } print_r($resultEvents);