php计算数字k在一段数字范围出现的次数

function digitCounts($k, $n) {
        static $total_nums = 0;
        $count = 0;
        for($i= 0;$i<=$n;$i++){
            $number = $i;
            //echo 0/10;   0
            while($number/10){//商
                if($number % 10 == $k){//余数
                   $count++;
                }
                $number = $number/10;
                $total_nums++;
            }
            if($number == $k){
               $count++;
            }
        }
        return $count;
}
print_r(digitCounts(5,25));   //3