php问题求帮助，以下函数返回值为何一直是100？

Question

$qc_q1=$_POST['q1'];
$qc_q2=$_POST['q2'];
$qc_q3=$_POST['q3'];
$qc_q4=$_POST['q4'];
$qc_q5=$_POST['q5'];
$qc_q6=$_POST['q6'];
$qc_q7=$_POST['q7'];
$qc_q8=$_POST['q8'];
$qc_q9=$_POST['q9'];
$qc_q10=$_POST['q10'];
$qc_Choice = array($qc_q1,$qc_q2,$qc_q3,$qc_q4,$qc_q5,$qc_q6,$qc_q7,$qc_q8,$qc_q9,$qc_q10);
$qc_Answer = array('a','d','d','b','b','c','d','d','c','c');
$qc_total = qcFunction($qc_Choice,$qc_Answer);
function qcFunction($qc_Choice,$qc_Answer){
    $total=0;
    for($i=0;$i<10;$i++)
    {
        if($qc_Choice[i]==$qc_Answer[i])
        {
            $total = $total + 10;
        }else
        {
            $total = $total + 0;
        }
    }
    return $total;
} 

Answer 1

 if($qc_Choice[i]==$qc_Answer[i])
 改成
  if($qc_Choice[$i]==$qc_Answer[$i])