Hackerrank repeated String

repeatedString.php

<?php

// Complete the repeatedString function below.
function repeatedString($s, $n) {
    $i = 0;
    $count = 0;
    while($i < strlen($s)){
        if ($s[$i] == 'a') {
            $count++;
        }
        $i++;
    }
    $total = floor($n / strlen($s));
    $total *= $count;

    if ($n%strlen($s)) {
        $r = $n % strlen($s);
        for ($i = 0; $i < $r; $i++) if ($s[$i] == 'a') $total++;
    }
    return $total;
}