Online PHP editor | output for nUbHe

<?php $sequence = "aabbcc"; $occurrences = array(); $sequences = str_split($sequence); // dn($sequences); $sequences_amount = array(); foreach ($sequences as $key => $char) { if(!isset($sequences_amount[$char])){ $sequences_amount[$char] = 1; }else{ $sequences_amount[$char]++; } } var_dump($sequences_amount); function sequenceCount($data = array()) { if(!isset($data) || empty($data) || (count($data) == 0))return; $count = NULL; foreach ($data as $char => $amount) { if($count == NULL){ $count = $amount; }else{ $count = $count * $amount; } } return $count; } $count = sequenceCount($sequences_amount); echo("\n\nResult:\n"); echo($count);