php时间调用有关问题

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--><?php   
function format_time($time){   
    $t=time()-$time;   
    $f=array(   
        '31536000'=>'年',   
        '2592000'=>'个月',   
        '604800'=>'星期',   
        '86400'=>'天',   
        '3600'=>'小时',   
        '60'=>'分钟',   
        '1'=>'秒'  
    );   
  
    foreach ($f as $k=>$v)   
    {           
        if (0 != $c=floor($t/(int)$k))   
        {   
            return $c.$v.'前';   
        }   
    }   
}   
echo format_time('1336880454');   
?>

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<?php 
$time1 = "2012-05-13 11:40:54";
$time2 = strtotime($time1);
echo $time2;//转换成时间戳格式
echo date('',$time2);//转换成标准日期格式
?>

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<?php while ($row = mysql_fetch_array($rs_tmmsm)) {?>
<?=date("Y-m-d <!--h:i-->",strtotime($row["pay_time"]))?>
<?php }?>

<?php function format_time($time){   
    $t=time()-$time;   
    $f=array(   
        '31536000'=>'年',   
        '2592000'=&gt;'个月',   
        '604800'=&gt;'星期',   
        '86400'=&gt;'天',   
        '3600'=&gt;'小时',   
        '60'=&gt;'分钟',   
        '1'=&gt;'秒'  
    );   
  
    foreach ($f as $k=&gt;$v)   
    {           
        if (0 != $c=floor($t/(int)$k))   
        {   
            return $c.$v.'前';   
        }   
    }   
}  
while ($row = mysql_fetch_array($rs_tmmsm)) {
    echo format_time(strtotime($row["pay_time"]));
}
?&gt; <div class="clear"></div>