$cityA = $_REQUEST[cityA];
$cityB = $_REQUEST[cityB];
$city = array(
"Indianapolis",
"New York",
"Tokyo",
"London"
);
$distance = array (
array (0, 648, 6476, 4000),
array (648, 0, 6760, 3470),
array (6476, 6760, 0, 5956),
array (4000, 3470, 5956, 0)
);
$result = $distance[$cityA][$cityB];
print <<The distance between $city[$cityA] and $city[$cityB] is $result miles.
HERE;
?>