//ข้อแรก
$str1 = "01";
$str2 = "10";
if($str1 == $str2 || $str1 == strrev($str2)){
	echo "เท่ากัน<br />";
}

//ข้อสอง
$a = array("01", "10", "11", "31","13","11", "07","70", "07");
$t = array();
for($i=0; $i<sizeof($a); $i++){
		if(!in_array($a[$i], $t) && !in_array(strrev($a[$i]), $t)){
			$t[] = $a[$i];
		}
}
print_r($t);

$a = array("01", "10", "11", "31","13","11", "07","70", "07");
$t = array();
for($i=0; $i<sizeof($a); $i++){
	for($j=0; $j<sizeof($a); $j++){
		if(!in_array($a[$i], $t) && !in_array(strrev($a[$i]), $t)){
			$t[] = $a[$i];
			break;
		}
	}
}
print_r($t);