投票系统 有人刷票 求大神帮忙解决解决方案

<?php<br />error_reporting(0);<br />session_start();<br />require_once 'config.php';<br />require_once COMMON_PATH.'Common.php';<br />$common = new Common();<br />date_default_timezone_set ('Asia/Shanghai');<br />$weil = strtotime("2013-08-07 23:59:59"); <br />$now = time();<br />if($weil-$now < 0){//投票时间过期<br />	echo 0;<br />	exit;<br />}<br /><br />$ip  = $common->getClientIp();<br />$id  = $_POST['id'];<br />$ipid=$ip.$id;<br />if($_SESSION['ipid']==$ipid||$_COOKIE['ipid']==$ipid){<br /><br />//$array = array('48','49','67','47'); <br />//if ( in_array($id,$array) ) {<br />		echo 2;<br />	} else {<br />		$tbName = TB_NAME;<br />		$limit_time = 3600;<br />		$arr = $common->getItems('id,addTime','20130618_ztao_jtsjip','id','desc',"where tpId='$id' and ip='$ip'");<br />		$row = false;<br />		if (count($arr) > 0) {<br />			$row = $arr[0];<br />		}<br />		if(!$row){<br />				$common->insertItems('20130618_ztao_jtsjip','tpId,ip,addTime',"'$id','$ip','$now'");<br />				$res = $common->updateItems("$tbName",'voteNum=voteNum+1',"$id");<br />				$_SESSION['ipid']=$ipid;<br />				setcookie("ipid","$ipid",time()+$limit_time);<br />				if($res == true){<br />					echo 1;//投票成功 <br />				}else{<br />					echo 3;<br />				}<br />			<br />		}else if(($now-$row['addTime'])>$limit_time){<br />			$common->insertItems('20130618_ztao_jtsjip','tpId,ip,addTime',"'$id','$ip','$now'");<br />			$res = $common->updateItems("$tbName",'voteNum=voteNum+1',"$id");<br />			$_SESSION['ipid']=$ipid;<br />			setcookie("ipid","$ipid",time()+$limit_time);<br />			if($res == true){<br />				echo 1;<br />			}else{<br />				echo 3;<br />			}<br />		}else if(($now-$row['addTime'])<$limit_time){<br />			echo 2;<br />		}else{<br />			echo 3;<br />		}<br />}<br /><br />?><br />