1-41的编程练习

<?php
header('content-type:text/html;charset=utf-8');
$Crowd='所有VIP会员';
$discount=80;
$commodity=1000;
$num=($discount*$commodity)/100;
$str=sprintf("元旦折扣！%s乐享%d%%优惠！<br/>原价%.2f￥的心动商品现价%.2f￥就能带回家哦！",$Crowd,$discount,$commodity,$num);
echo $str;

请问能否这样做？