3v4l.org

run code in 300+ PHP versions simultaneously
<?php $words=['MVW','MWAH','MWAH','MYW','MW','MY9AH','MYQAH','MYQAH','MY9AH','MYQAH', 'MYQAH','MWAH','MYQAH','MYSWI','MYQAH','MYQAH','MW','MW','MW','MW']; $chars=array_map('str_split',$words); usort($chars,function($a,$b){return sizeof($b)-sizeof($a);}); $result=''; foreach($chars[0] as $col=>$not_used){ $occurrences=array_count_values(array_column($chars,$col)); // no NULL values arsort($occurrences); $result.=key($occurrences); } echo $result;

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