求个PHP列出周日期代码,该怎么解决

<?php<br />
//打印周五<br />
$week = getdate();<br />
//echo $week['wday'];<br />
if($week['wday']==5)<br />
//echo $week['year'].'年'.$week['mon'].'月'.$week['mday'].'日';<br />
//echo $week[year].'年'.$week[mon].'月'.$week[mday].'日';<br />
<br />
for($i=1;$i<=20;$i++)<br />
{<br />
$j=$i*-7;<br />
$k=$j+7;<br />
echo date("Y年m月d日",strtotime($j." days"));<br />
echo "->".date("Y年m月d日",strtotime($k." days"));<br />
echo "<br />";<br />
}<br />
?>

$s='2013-05-31';<br />
$current=date("Y-m-d");<br />
while($current>=$s){<br />
    $ar[]=$current;<br />
	$current=date("Y-m-d",strtotime("$current -7 day"));<br />
}<br />
	for($i=0;$i<count($ar)-1;$i++){<br />
	   echo $ar[$i+1].'->'.$ar[$i]."\n";<br />
	}

for($i=0,$t=-7; $i<20; $i++,$t-=7) {<br />
  echo date('Y-m-d -> ', strtotime("$t day"));<br />
  echo date('Y-m-d', strtotime(($t+7)."day")) . '<br>';<br />
}