Online PHP editor | refs for 14LHh

<?php $arr = [ [ 'cards1' => [ 'A', 'b', 'c' ], 'cards2' => [ 'A', 'e', 'd' ], 'cards3' => [ 'A', 'o', 'l' ] ], [ 'cards1' => [ 'A', 'b', 'c' ], 'cards2' => [ 'A', 'r', 'c' ], 'cards3' => [ 'A', 'bbb', 'yyy' ] ], [ 'cards1' => [ 'B', 'bbb', 'B' ], 'cards2' => [ 'B', ], 'cards3' => [ 'B', ] ] ]; $set = []; $except = []; foreach($arr as $data){ foreach($data as $key => $cards){ if($key === 'cards1'){ $except[$data[$key][0]] = true; break; } } } foreach($arr as &$data){ foreach($data as $key => &$cards){ foreach($cards as $index => $value){ if(isset($set[$value]) && !isset($except[$value])) unset($cards[$index]); else $set[$value] = true; } } } print_r($arr);