<?php

$r_dom = 'google.com'; //Domain name of the referrer
$r_page = '/url?sa=t&q=keyword+1&cp=1'; //Referrer Page

if(preg_match('/(google|yahoo|bing|(search|images|videos).geegain|mywebsearch|ask|search.aol|alltheweb|search.netscape|baidu|blekko|duckduckgo).[a-z\.]{2,6}/i',$r_dom,$r_se)){
$r_se = $r_se[1];
if(preg_match('/\./',$r_se)){
	$r_se = explode('.',$r_se);
	$r_se = $r_se[1];
}
switch($r_se){
	case "google":
		$r_se_q[0]="q";
		$r_se_q[1]="p";
		break;
	case "yahoo":
		$r_se_q[0]="p";
		$r_se_q[1]="q";
		break;
	case "mywebsearch":
		$r_se_q[0]="searchfor";
		break;
	case "baidu":
		$r_se_q[0]="wd";
		break;
	case "blekko":
		$r_se_q[0]=1;
		break;
	default:
		$r_se_q[0]="q";
		break; //geegain,bing,ask,alltheweb
}
if($r_se=='blekko'){
	$se_keyword = preg_match('/^\/ws\/(.*)(\/|$)/',$r_page,$se_parse_arr);
}else{
	parse_str(preg_replace('/^\/(.*)\?/','',$r_page),$se_parse_arr);
}

$se_keyword = $se_parse_arr[$r_se_q[0]];
if($se_keyword==null){
	$se_keyword = $se_parse_arr[$r_se_q[1]];
}
$se_keyword = urldecode($se_keyword);

echo $se_keyword;

}

?>